My favourites

Check an API description in JSON or YAML without uploading it.

Model a school report with several subjects across one to four grading periods.

Compare both connections with a circuit diagram, tolerances and individual currents and powers.

Replace a text fragment in a pasted or imported document.

Extract PDF tables into an XLSX workbook, with a separate sheet for each detected table and local processing.

Alternate pages from front and back scans, optionally reverse the backs and check the final order before downloading.

Separate scanned spreads vertically or horizontally, adjust the cut and choose the reading order without rasterizing every page.

Extract selectable PDF text as UTF-8 TXT, choose pages, inspect the preview and copy the result without OCR.

Estimate car payments with a down payment, trade-in, taxes, fees and a full amortization schedule.

Estimate calories burned walking, running, cycling or doing everyday activities using your weight and workout time.

Find the size of a copper cable from its current-carrying capacity and voltage drop, with the circuit breaker, installation method and temperature.

Convert US cups, tablespoons and teaspoons to grams by ingredient: flour, sugar, butter, milk and more.

Convert pixels to centimetres and back at a given resolution (DPI), or measure the print size of an image.

Calculate the 2-digit key of a French social security number or check a complete number.

Build a French intra-community VAT number from a SIREN or SIRET, or check its key.

Record, trim, adjust volume, apply effects and convert audio in one editor.

Explore possible child blood types from the parents' blood groups.

Remove overly long silent sections from an audio file.

Record your voice directly in the browser without uploading it.

Balance the reaction, enter reactant masses and calculate the limiting reagent, theoretical product and percent yield.

Calculate pressure, volume, amount of gas or temperature with the ideal gas law.

Calculate a projectile trajectory from initial speed, launch angle, initial height and gravity.

Calculate fall time and final speed from height, initial downward velocity and gravity.

Calculate remaining quantity, elapsed time, half-life or initial quantity with exponential decay.

Decode resistor bands to get resistance, tolerance and, for 6 bands, temperature coefficient.

Turn a wide table into long format while preserving identifier columns.

Create a new numeric column from a formula that references other table columns.

Turn nested JSON objects into explicit path columns ready for tabular use.

Enter any two values among voltage, current, resistance and power to calculate the other two automatically.

Calculate a dilution concentration or volume from three known values using C₁V₁ = C₂V₂.

Calculate density, mass or volume from any two known values with automatic unit conversion.

Calculate average speed, distance or elapsed time from any two known values with automatic unit conversion.

Calculate net force, mass or acceleration from any two known values using F = ma.

Calculate molar concentration, amount of substance or solution volume from any two known values.

Calculate kinetic energy, mass or speed from any two known values using Eₖ = ½mv².

Calculate molar mass from a chemical formula, then convert mass to moles or moles to mass.

Calculate pH, pOH, hydronium concentration or hydroxide concentration at 25 °C from one known value.

Automatically balance a neutral molecular chemical equation with the smallest whole-number coefficients.

Add up the hours you worked this week, breaks deducted, in hours and minutes and in decimal hours.

Count the hours of a shift that fall in the night period (9 pm – 6 am by default, French rule) and estimate a configurable night premium.

Convert a part-time percentage into hours per week, month and year, or find the percentage of a weekly schedule.

Add several hour-and-minute durations and get the total as h:mm, decimal hours and minutes.

Estimate French RTT days: a 39-hour week against the 35-hour reference, or rest days under a 218-day annual package for a given year.

Work out the paid-leave days earned in France over the reference period, including during non-occupational sick leave.

Estimate pay for a Sunday or public holiday worked under French law: double pay on 1 May and mayor’s Sundays, +30 % in large food stores, or your agreement’s rate.

Create a monthly XLSX timesheet: one row per day, start and end times, breaks, hours worked, decimal hours and totals calculated by formulas.

Calculate hours worked above a French part-time contract, their 10% and 25% premiums and the resulting pay.

Remove a white or solid-color background and get a transparent PNG, without uploading your image.

Resize an image to the right dimensions for Instagram, Facebook, LinkedIn, YouTube, X, TikTok or Pinterest in one click.

Crop a photo into a circle, round its corners and add a border, with a transparent background.

Convert hours and minutes to decimal hours or hundredths and back.

Work out overtime above 35 hours, the +25 % and +50 % premiums of French law or your own rates, and the annual quota.

Turn overtime into replacement rest or work out the mandatory rest due beyond the annual overtime quota under French law.

Find a fourth proportional by cross multiplication, solve inverse proportion, or simplify a ratio.

Add, subtract, multiply, divide and simplify fractions, with every step shown.

Find the GCF (GCD) and LCM of two or more numbers, with the Euclidean algorithm and prime factorization.

Paste a list of numbers to get its mean, median, mode, range, sum and count.

Calculate the standard deviation and variance of a data set, for a population (σ) and for a sample (s), with the deviations table.

Turn a number of correct answers into a percentage score and count your mistakes, for a multiple-choice test, quiz or exam.

Calculate a credit-weighted GPA from the grade points of each course, on a 4.0 scale or another scale.

Find the GPA you need over your next credits to reach a target cumulative GPA, and see whether the goal is still possible.

Rescale a grade out of 20, 10, 100 or any maximum to another scale, with its percentage, by simple proportion.

Calculate your attendance rate, how many more classes you can miss and the classes you need to reach your target.

Estimate your body fat percentage with the U.S. Navy method from body measurements, then see your fat mass and lean body mass.

Estimate lean body mass with Boer, James and Hume, with an optional comparison from a known body-fat percentage.

Calculate FFMI, height-normalized FFMI and FMI from height, weight and body-fat percentage.

Calculate your running pace, finish time or distance, predict race times from 5K to marathon and get your split times, in miles or kilometres.

Calculate average CAC and the payback period for customer acquisition spend.

Estimate LTV from monthly revenue, gross margin, and monthly churn.

Calculate monthly burn rate and the number of months of cash runway remaining.

Calculate annual inventory turnover and average days of inventory.

Calculate DIO, DSO, DPO, and cash conversion cycle days.

Validate JSON-LD syntax and detect types, entities, and structural warnings.

Classify internal, external, and relative HTML links and inspect nofollow, sponsored, and ugc.

Compare two sitemaps or URL lists and identify added and removed URLs.

Measure term frequency, phrase occurrences, and density in text or HTML.

Generate 301 rules for Apache, Nginx, Netlify, or Vercel from a URL mapping.

Compute an HMAC-SHA-1, SHA-256, SHA-384 or SHA-512 in hex or Base64 and verify a webhook signature.

Encrypt and decrypt text with a password using AES-256-GCM, right in your browser.

Decode a PEM X.509 certificate or CSR: subject, issuer, dates, SANs, public key and SHA-256 fingerprint.

Derive a salted PBKDF2-SHA-256 or SHA-512 password hash, or verify a password against an encoded value.

Generate secure random tokens from 8 to 256 bytes in hex, Base64 or Base64URL, with an optional prefix.

Generate a PKCE code_verifier, its S256 code_challenge and a state for your OAuth authorization request.

Generate TOTP 2FA codes from a Base32 secret, build the otpauth:// URI and verify a 6- or 8-digit code.

Inspect a JWK or JWKS: kid, kty, alg, use, RFC 7638 thumbprint and a warning when private key material is exposed.

Estimate your basal metabolic rate in kcal and kJ, and compare the Mifflin-St Jeor, Harris-Benedict and Katch-McArdle equations.

Work out your bra size from your underbust and bust measurements, with UK, US, EU, French, Italian and Australian sizes and sister sizes.

Calculate your maximum heart rate (Tanaka, 220 − age, Gulati) and your five training zones, with the Karvonen method if you know your resting heart rate.

Calculate your body mass index from height and weight, with adult reference ranges and clearly explained limitations.

Estimate your total daily energy expenditure from your activity, compare the five levels and get guideline intakes for each weight goal.

Find your ideal weight for your height: healthy BMI range and the Devine, Robinson, Miller, Hamwi, Lorentz, Broca, Creff and Monnerot-Dumaine formulas.

Calculate your waist-to-hip ratio, place your waist size on the WHO cut-offs and, with your height, get the waist-to-height ratio recommended by NICE.

Calculate body surface area in m² from height and weight, with the Mosteller, Du Bois, Haycock, Gehan-George and Boyd formulas.

Convert Excel, CSV, or JSON into a copy-ready Markdown table.

Turn Excel, CSV, or JSON into semantic HTML table markup.

Generate SQL INSERT statements from Excel, CSV, or JSON.

Cross a row dimension with a column dimension, then calculate count, sum, average, minimum, or maximum.

Swap rows and columns in an Excel, CSV, or JSON table.

Calculate a weighted average and the next grade needed to reach your target.

Calculate the Spanish university access grade out of 10 and admission grade out of 14.

Calculate the Portuguese nota de candidatura on the 0–200 scale.

Calculate the Italian Maturità final score out of 100.

Calculate your IB score out of 45 and check the main Diploma passing criteria.

Calculate UCAS points for A levels, AS levels and the EPQ.

Convert ECTS credits into study workload and track progress toward a credit target.

Estimate mortar volume and bags for a brick or block wall.

Estimate bar counts, linear length, and weight for a reinforcement grid.

Estimate studs, plates, and timber length for a framed wall.

Calculate rafter length, count, and total timber for a simple gable roof.

Estimate asphalt volume, tonnage, and truckloads for a rectangular area.

Simulate your 2027 French Bac average, result, honours and the grades you still need.

Calculate your 2027 DNB average, result, honours and the grades you still need.

Rotate an image left, right, or to a custom angle directly in your browser.

Flip an image horizontally or vertically directly in your browser.

Expand or reduce the canvas around an image without resizing its content.

Adjust brightness, contrast, saturation, exposure, temperature, hue, shadows, highlights, and sharpness.

Select a specific area of an image, then blur or pixelate it locally.

Add text, arrows, and highlights to an image directly in your browser.

Crop, resize, add captions or watermarks, apply effects, and optimize an image in one editor.

Lighten an image by setting its quality or aiming for a size in KB, with the final size shown before download.

Split an image into tiles using a chosen number of rows and columns.

Combine several images into a grid with configurable spacing and background.

Add top and bottom captions to an image directly in your browser.

Apply blur, pixelation, grayscale, or sepia with adjustable intensity.

Validate an IBAN checksum or calculate its check digits.

Calculate working capital requirement, working capital, net cash and WCR days.

Calculate French EBE, EBITDA and both margins as a percentage of revenue.

Convert an Umm al-Qura Hijri date to a Gregorian date, or the other way round, with weekday and an after-sunset option.

Calculate Friday candle-lighting and Havdalah times for your city and the week you choose.

Convert a Hebrew (Jewish) calendar date to a Gregorian date, or the other way round, with Adar I and Adar II, the date in Hebrew and an after-sunset option.

Find the date of Easter for any year, Western and Orthodox, with Ash Wednesday, Ascension, Pentecost and the related holidays.

Find today’s Rahu Kalam (Rahu Kaal) for your city from the actual local sunrise and sunset.

Estimate Zakat at 2.5% from assets, debts and your chosen Nisab standard.

Convert a Persian (Solar Hijri, Jalali) calendar date to a Gregorian date, or the other way round, with the date in Persian, leap year and Nowruz date.

Convert a date between the Gregorian calendar and the Meiji, Taishō, Shōwa, Heisei and Reiwa eras.

Convert a Julian (Old Style) calendar date to a Gregorian date, or the other way round, with the gap in days, the weekday and the Julian Day Number.

Find when golden hour and blue hour start and end, morning and evening, for any place and date.

Work out the length and direction of an object’s shadow from the place, date, time and its height.

Get the 8 day and 8 night Choghadiya for your city, calculated from the actual local sunrise and sunset.

Convert dates between the 13-month Ethiopian calendar and the Gregorian calendar.

Convert dates between the 13-month Coptic calendar and the Gregorian calendar.

Convert dates between the Indian national Saka calendar and the Gregorian calendar.

Convert dates between the Nepali Bikram Sambat calendar and the Gregorian calendar.

Match two tables on a shared column without uploading your files.

Raise or lower audio pitch by semitones without changing duration.

Calculate how much to save regularly to reach a target amount.

Adjust bass, midrange and treble directly in your browser.

Calculate the direction of the Kaaba from your city or coordinates: bearing in degrees from true north and distance to Makkah.

Calculate Fajr, Sunrise, Dhuhr, Asr, Maghrib and Isha times for your city.

Extract the tables in a PDF into a CSV file to open in Excel, LibreOffice or Google Sheets.

Convert the text of a PDF into a structured HTML page with headings, paragraphs and tables.

Turn the text of a PDF into structured XML (pages, headings, paragraphs, tables), ready for automated processing.

Add text, annotations, images, drawings or a signature directly to your PDF.

Add a visual stamp such as APPROVED, PAID or CONFIDENTIAL.

Draw freehand with the color and line width you choose.

Permanently hide sensitive areas by rebuilding the document.

Add text to one or more pages at a precise position.

Highlight or frame an area and add a visible note.

Add recurring text with automatic page numbers.

Fill in the fields of an interactive PDF form on screen, then lock the answers if needed.

Analyze key SEO signals in HTML locally.

Preview a search result from a title and meta description.

Detect noindex, nofollow and canonical inconsistencies from HTML.

Convert a date and time from one time zone to another, daylight saving time included.

Convert a date between MM/DD/YYYY, DD/MM/YYYY and ISO YYYY-MM-DD, in both directions.

List every date between two endpoints, every N days, weeks, months or years.

Find meeting slots that fall within the working hours of two time zones.

Calculate the business hours between two dates from your daily working hours.

Find the weekday (Monday, Tuesday…) of any past or future date.

Express the gap between two date-times as “3 days ago” or “in 2 hours”.

Find the number of a day within its year (1 to 365 or 366) and the days remaining.

Get the next N dates of a daily, weekly, monthly or yearly recurrence.

Calculate net present value from an initial investment, future cash flows and a discount rate.

Estimate internal rate of return from an initial investment and future cash flows.

Calculate how long an investment takes to recover, with simple and discounted cash flows.

Repair a damaged PDF locally by rebuilding recoverable internal structures.

Compare two PDFs page by page and measure their visual differences locally.

Rearrange PDF pages into spreads ready for duplex booklet printing.

Recognize text in a scanned PDF and create a searchable PDF directly in your browser.

Estimate how much you can borrow and the home price you may afford from income, debts, down payment, rate and term.

Calculate your total debt-to-income ratio, housing ratio and remaining monthly borrowing room.

Automatically detect and remove blank PDF pages directly in your browser.

Overlay the pages of one PDF onto another locally, with adjustable opacity.

Remove comments, highlights and other page annotations without changing the main content.

Inspect pages, size, version, metadata, forms, annotations and active elements in a PDF.

Control printing, modifications and content extraction with an AES-256 owner password.

Automatically split a PDF by a maximum number of pages or a target file size.

Place 2, 4, 6 or 9 PDF pages on each A4 or Letter sheet.

Correct contrast, brightness and saturation or convert a PDF to grayscale.

Calculate the gross and net yield of a rental property investment.

Calculate sales commission from revenue and the applicable commission rate.

Estimate the day rate you need to reach a target monthly net income.

Add UTM parameters to a campaign URL.

Create hreflang tags from localized page versions.

Create an XML sitemap from a list of URLs.

Preview an image as it may appear with different types of color vision deficiency.

Compare two images with a before/after slider, side by side or by highlighting the pixels that differ.

Convert an image to Base64/Data URI and convert Base64 back to an image.

Calculate CAGR between an initial and a final value.

Calculate simple interest and final amount.

Estimate how inflation affects an amount.

Remove unwanted pages from a PDF directly in your browser.

Automatically add page numbers to your PDF document.

Add a text watermark to every page of a PDF locally in your browser.

Edit or remove common PDF metadata directly in your browser.

Crop PDF pages by drawing the area to keep, directly in your browser.

Resize every PDF page to a standard or custom size locally in your browser.

Reduce PDF file size locally with lossless optimization or stronger visual compression.

Flatten form fields or create a visually fixed PDF directly in your browser.

Recover raster images embedded in a PDF without converting whole pages to images.

Clean a PDF locally by removing metadata, JavaScript, automatic actions and embedded attachments.

Extract selectable text from a PDF and convert it to Markdown locally, without OCR or uploading the document.

Encrypt a PDF locally with a password and AES-256 without uploading your document.

Remove PDF password protection locally when you know the current password.

Generate a JSON Schema from a JSON example locally in your browser.

Convert HTML into readable portable Markdown directly in your browser.

Convert Markdown into clean HTML directly in your browser.

Read the content of a QR code from an image directly in your browser.

Combine multiple images into an animated GIF directly in your browser.

Reduce audio file size by choosing an output format and bitrate.

Normalize the perceived loudness of an audio file to a LUFS target.

Speed up or slow down an audio file without changing pitch.

Add fade-in and fade-out effects to an audio file.

Convert audio to mono or stereo.

Resample audio to 44.1 kHz, 48 kHz or another rate.

Reverse an audio file directly in your browser.

Split the left and right channels of stereo audio into two mono files.

Convert a WAV file to MP3 locally in your browser.

Convert an M4A file to MP3 locally in your browser.

Convert an MP3 file to WAV PCM locally in your browser.

Convert a FLAC file to MP3 locally in your browser.

Convert an OGG file to MP3 locally in your browser.

Extract and convert WebM audio to MP3 locally in your browser.

Calculate steps, riser height, going, angle and the Blondel formula.

Estimate decking boards, joists, fixings and waste.

Calculate screed volume, dry mix, cement, sand and bags.

Estimate bricks, joints, wall volume and mortar.

Calculate sloped roof area and the number of tiles required.

Calculate fence panels, posts and footing concrete.

Calculate render kilograms and bags from area, thickness and consumption per mm.

Calculate pavers, packs, joints and bedding volume.

Convert audio files locally to MP3, WAV, FLAC, OGG, M4A or Opus.

Keep only the useful part of an audio file.

Increase or reduce the volume of an audio file.

Join multiple audio files in the selected order.

Calculate concrete volume and the cement, sand, gravel or bags required.

Calculate paintable area, litres required and paint containers to buy.

Calculate tiles, boxes and quantities to order.

Calculate concrete blocks, pallets and mortar bags for a wall.

Calculate gravel volume, weight, bags or bulk bags to buy.

Convert slope between percent, degrees, rise, length and ratio.

Calculate plasterboards, tracks, studs and screws for a partition or ceiling.

Calculate packs, underlay, surplus and skirting boards for your floor.

Calculate area, volume, packs and thermal resistance R of insulation.

Calculate drops and rolls from dimensions and pattern repeat.

Add or subtract days, weeks, months or years from a date and get the resulting date with its day of the week.

Count the business days between two dates and shift a date by a number of working days, for a Monday–Friday or other working week.

Calculate the duration between a start time and an end time, even past midnight.

Convert milliseconds, seconds, minutes, hours, days, weeks and working days.

Find out how many days are left until a date, or how many have passed since, with the equivalent in weeks.

Find the ISO week number of a date, its ISO year and the Monday-to-Sunday dates.

Instantly calculate net price, VAT and gross price in either direction.

Calculate ROI, net gain and the total cost of an investment.

Calculate the revenue and sales volume needed to cover your costs.

Calculate a discounted price, the amount saved, or the discount percentage.

Calculate pay from hours worked × hourly rate or convert hourly, weekly, monthly and annual salary.

Estimate net pay before income tax from gross salary, or calculate gross pay from net.

Calculate your new salary after a raise or find the percentage needed to reach a target salary.

Calculate capital growth with compound interest and regular contributions.

Calculate gross margin, markup rate, margin rate and selling price.

Find a missing length with the intercept theorem, also called the basic proportionality or side splitter theorem, or test parallel lines with its converse.

Convert yards to meters and meters to yards with the exact factor 1 yard = 0.9144 m, for American football, golf, fabric and swimming pools.

Convert pressure from psi to kilopascals and back with the factor 1 psi = 6.894757 kPa and a table of common pressures.

Convert knots to kilometers per hour and back with the exact factor 1 knot = 1.852 km/h, for sailing, aviation and marine weather.

Convert kilowatt-hours to joules and joules to kWh with the exact factor 1 kWh = 3,600,000 J, plus examples from electricity bills and batteries.

Write a number in words in English, French, Spanish, German, Italian or Portuguese, or turn written words back into digits.

Write a euro amount in words for a cheque, or turn a written amount back into figures.

Simulate a loan, calculate monthly payments and total cost, and view a complete amortization schedule.

Convert centimeters to inches and inches to centimeters with the exact factor 1 inch = 2.54 cm, for screens, clothing sizes and product dimensions.

Convert kilograms to pounds (lb) and pounds to kilograms with the exact factor 1 lb = 0.45359237 kg, plus a table of common values.

Convert millimeters to inches and inches to millimeters with the exact factor 1 inch = 25.4 mm, for fasteners, tools, wheels and tires.

Convert degrees Celsius to Fahrenheit and back with the exact formula °F = °C × 1.8 + 32, plus a table of common temperatures.

Convert kilometers to miles and miles to kilometers using the exact factor 1 mi = 1.609344 km, with a table of common values.

Convert meters to feet and feet to meters with the exact factor 1 foot = 0.3048 m, for height, altitude, construction and aviation.

Convert feet to inches and inches to feet with the exact ratio 1 foot = 12 inches, for heights, ceilings and construction dimensions.

Convert ounces (oz) to grams and grams to ounces with the exact factor 1 oz = 28.349523125 g, plus a kitchen-friendly conversion table.

Convert pounds to grams and grams to pounds with the exact factor 1 lb = 453.59237 g, plus a kitchen-friendly conversion table.

Convert liters to US gallons and US gallons to liters with the exact factor 1 US gal = 3.785411784 L, plus a table of common values.

Convert cubic meters to liters and liters to cubic meters with the exact factor 1 m³ = 1,000 L, plus examples for water, pools and tanks.

Convert kilometers per hour to miles per hour and back, using the exact factor 1 mph = 1.609344 km/h, with a table of common speed limits.

Find the area of a square from its side (s²) or its diagonal (d² ÷ 2).

Find the distance around a square from its side (4 × s) or its diagonal (2√2 × d).

Multiply length by width to get the area of a rectangle, even with different units for each side.

Find the distance around a rectangle from its length and width: P = 2 × (L + W).

Find the area of a triangle from the base and height, all three sides (Heron's formula) or two sides and the included angle.

Add up the three sides of a triangle, or find the third side with the law of cosines from two sides and the included angle.

Find the area of a circle from its radius, diameter or circumference, in the unit of your choice.

Find the circumference of a circle from its radius or diameter, with the formula C = 2πr explained.

Find the hypotenuse or a missing leg of a right triangle, or check whether a triangle is right-angled with the converse, with a full worked solution.

Find a percentage of any value: 20% of 150, 8% sales tax on a price or a 20% tip on a bill.

Find what percentage a value is of a total: 30 out of 150, a test score, a share of your budget.

Find the percentage increase between two values, add X% to a value or work back to the value before the increase.

Find the percentage decrease between two values, reduce a value by X% or work back to the value before the decrease.

Convert square meters to square feet and back with the exact factor 1 ft² = 0.09290304 m², for real estate and home projects.

Convert hectares to acres and acres to hectares with the exact factor 1 acre = 4,046.8564224 m², plus a table of common land areas.

Convert liters to British imperial gallons and UK gallons to liters with the exact factor 1 UK gal = 4.54609 L, plus a table of common values.

Convert pressure from bar to psi and back, using the exact factor 1 bar = 14.5038 psi, with a table of common tyre and equipment pressures.

Convert kilowatts to mechanical horsepower (hp) and metric horsepower (PS) without mixing them up: 1 hp = 745.699872 W, 1 PS = 735.49875 W.

Convert decimal megabytes and gigabytes (MB, GB) to binary mebibytes and gibibytes (MiB, GiB): 1 GB = 1,000,000,000 bytes, 1 GiB = 1,073,741,824 bytes.

Place a PNG or JPEG image on the PDF page you choose.

Place a signature image on the PDF page you choose.

Choose a 2D shape or 3D solid, enter the dimensions you know and get the area, perimeter, diagonals, angles, surface area and volume.

Generate TypeScript interfaces, types, Zod schemas, or JSON Schema from sample JSON.

Remove duplicate CSV rows using the columns you choose as matching criteria.

Split a CSV file into smaller files using the size or groups you choose.

Compare two CSV files to quickly identify rows and values that differ between them.

Merge multiple CSV files into one table while keeping columns aligned consistently.

Filter CSV rows by column using text, exact values, or numeric conditions.

Sort CSV rows by a selected column in ascending or descending order.

Select the CSV columns you want to keep in the final result.

Rename one or more CSV columns without changing the row data.

Profile every CSV column with detected type, missing values, cardinality, and descriptive numeric statistics.

Generate a complete cURL command from an HTTP request.

Build custom HTTP headers and get output ready to use in your requests.

Build a complete HTTP API request with method, URL, parameters, headers, and body.

Analyze HTTP headers to review security, caching, CORS, and cookie behavior.

Create the Authorization: Basic header from a username and password, or decode an existing header.

Create and sign an HS256, HS384 or HS512 JWT from a header, a JSON payload and a secret.

Create a favicon.ico and a site’s PNG icons (16 to 512 px) from one image, in your browser.

Validate CSV structure and quickly identify problematic rows or columns in your data.

Generate the SRI integrity attribute of a script or stylesheet from pasted content, a file or a CDN URL.

Validate a JSON document against a schema and locate every error precisely.

Build a standard cron expression, understand it and preview its next execution times.

Write Markdown and instantly preview the rendered HTML.

Convert an integer between bases 2 and 36: binary, octal, decimal, hexadecimal or a custom base, with negatives and very large integers.

Convert Unix permissions between octal and symbolic notation and generate a chmod command.

Create a .gitignore file from presets for your technologies and tools.

Find a MIME type from an extension or the other way around.

Reduce SVG markup locally while keeping the graphic editable.

Create SEO, Open Graph and Twitter/X tags for a web page.

Create a clear robots.txt file to guide web crawlers.

Calculate proportional dimensions for images and videos.

Build a Content Security Policy directive by directive, with HTTP header, meta tag and warnings.

Generate HSTS, nosniff, Referrer-Policy, Permissions-Policy, COOP/COEP/CORP and X-Frame-Options for Nginx or Apache.

Create a modern password policy: length, blocklists, passphrases, expiration and attempt limits.

Create a QR code locally for text, a URL, email, phone number or Wi-Fi network.

Extract a dominant color palette from an image without uploading it to a server.

Draw a frame on the image, lock a ratio (1:1, 4:5, 16:9…) and download the cropped part.

Create multiple image widths and automatically generate srcset and picture markup.

Add text or a logo locally with adjustable position, opacity, size, and rotation.

Convert SVG files to PNG, JPEG or WebP with preview and output settings.

Create JSON-LD structured data ready to embed in a web page.

Identify the browser, operating system, device and bots in a User-Agent string.

Convert a color between HEX, RGB, and HSL with equivalent values.

Measure contrast between two colors and check WCAG AA and AAA levels.

Format and validate a YAML document to improve readability and detect common errors.

Format, minify, and validate an XML document directly in your browser.

Calculate an exact age in years, months and days from a date of birth and any reference date.

Analyse a text and get its number of words, characters, lines, sentences and paragraphs.

Draw up to 1,000 random integers or decimals in a range, with or without repeats, for raffles, dice or sampling.

Extract every email address found in a text and remove the duplicates.

Extract every URL from text and automatically remove duplicate addresses.

Format HTML or remove ordinary comments locally while retaining text whitespace and script content. No page execution or upload is required.

Randomly shuffle the lines of a text or a list in a few seconds.

Format or minify CSS to improve readability or reduce file size.

Test a regular expression against text and inspect the matches it returns.

Format queries using the formatter’s general SQL dialect without a database connection. Processing runs locally in your browser.

Format JavaScript, TypeScript or JSX for easier reading without executing code. Processing runs locally in your browser.

Format Markdown text into a cleaner and more consistent structure for easier review.

Check how strong a password is: entropy, weak patterns, estimated time to crack and advice.

Verify a JWT signature with an HMAC secret or a JWK, JWKS or PEM public key, then check exp, nbf, iss and aud.

Check whether two hashes or checksums match, regardless of case, spaces or colons.

Compare two texts line by line and quickly spot additions, deletions and changes.

Automatically extract every number found in a text and get them back as a list.

Automatically extract the numeric dates found in a text and get them back as a list.

Estimate how easy a text is to read with the Flesch reading ease score.

Encode or decode common HTML entities to convert special characters in text.

Convert JSON data to YAML or YAML data to JSON directly in your browser.

Convert JSON data to XML or XML data to JSON directly in your browser.

Query JSON data with a simple JSONPath expression.

Test an XPath expression against XML and immediately inspect the matching results.

Compare two JSON documents and highlight structural differences.

Convert tabular text between comma-separated and tab-separated formats.

Find duplicate lines, count occurrences and export a clean summary.

Validate, normalize and inspect web addresses locally.

Convert length, weight, volume, temperature, pressure, energy, fuel economy, digital storage and electrical units with exact factors.

Calculate X% of a value, what percentage a value is of a total, the percent change between two values or the original value before a change.

Calculate the time between two dates in years, months and days, in total days and in weeks.

Generate realistic fake datasets in JSON, CSV or SQL.

Build a complementary, analogous, triadic or monochromatic palette from one color.

Read a photo’s EXIF data: camera, settings, capture date and GPS position.

See a photo’s EXIF and GPS data, then download a copy that no longer contains it.

Combine several images into a single PDF document.

Convert PDF pages into individual images ready to download directly in your browser.

Convert text between LF, CRLF and CR line endings.

Parse URL parameters or build a query string from key-value pairs.

Resize an image by setting its exact width and height before downloading the result.

Merge multiple PDF files in the order you select them to create one combined document.

Convert an image to PNG, JPEG, or WebP and adjust output quality before download.

Select the pages you want to keep and create a new PDF containing only that selection.

Turn PDF pages the right way up in quarter turns, page by page, with no loss of quality.

Visually reorder PDF pages with drag and drop or keyboard controls.

Split a PDF into multiple files using the pages or page ranges you choose.

Create brand, product, project or domain names from your keywords – not personal names.

Remove duplicates, empty rows and unnecessary spaces.

Merge multiple Excel or CSV files into one table with automatic column alignment.

Compare two Excel or CSV files using a key column and spot the differences.

Convert Excel, CSV, and other spreadsheet formats directly in your browser.

Split an Excel file into multiple sheets based on values from a selected column.

Encode text as Base64 or decode a Base64 string back to its original content.

Encode or decode a URL, its parameters, and any special characters it contains.

Count how many times each value appears in a list and spot the most frequent items at a glance.

Merge two lists into a single set of lines ready to copy or reuse.

Split a long list into groups of a fixed size, based on the number of items you choose.

Convert a Unix timestamp to a readable date and time, or a date to a timestamp, in seconds or milliseconds.

Compute MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of a text or file in one go.

Automatically add a number in front of every line, in the format you choose.

Automatically remove empty lines and lines containing only spaces from a text.

Turn a title or phrase into a clean slug that is ready to use in a URL.

Convert CSV data to JSON or JSON to CSV while preserving useful structure.

Compare two lists to find the items they share and the ones that differ.

Remove duplicate lines from a list while keeping one occurrence of each value.

Sort the items of a list alphabetically or numerically, in ascending or descending order.

Format, minify, and validate JSON to make it easier to read or more compact.

Decode a JWT to read its header, payload, claims and expiration dates.

Generate one or more random UUID v4 identifiers instantly and copy them when needed.

Generate strong random passwords from 8 to 128 characters, with the entropy shown.

Remove extra spaces, repeated tabs and empty lines from copied text.

Generate Lorem Ipsum placeholder text for mockups, prototypes and layout tests.

Convert text to lowercase, UPPERCASE, Title Case or other common case styles.