Dates & time
Sun shadow calculator
Calculate shadow length and bearing from the local solar position, including Sun altitude and azimuth.
Sun shadow calculator
Estimate where an object’s shadow falls and how long it is at a specific local date and time.
City search uses the Open-Meteo geocoding service.
Result
Calendar and solar results are calculated locally in your browser.
Was this tool useful?
How does this tool work?
Estimate where an object’s shadow falls and how long it is at a specific local date and time.
The tool computes Sun altitude and azimuth from the location, time zone, date and local time. Shadow length is height ÷ tan(solar altitude), and the shadow direction is opposite the Sun’s azimuth. The result depends on the conventions of the calendar or phenomenon being calculated. The engine validates the entered values, applies the relevant conversion rules or astronomical formulas, and returns a localized result. For solar calculations, geographic position, time zone and date can materially change the output.
How to use this tool
Enter the inputs
Provide the requested date and values.
Adjust the context
Choose the conversion direction or location when required.
Read the result
The calculation runs locally and can be repeated with new values.
Use cases
Conversion and verification
Get a value that would be tedious to compute manually.
Planning
Prepare a date, photo session or observation from precise inputs.
Documented comparison
Compare a date, light window or measurement with another source while keeping the calculation inputs and assumptions visible.
Tips and best practices
- Check the date and time zone for Sun-dependent calculations.
- For historical or official use, consider the local conventions described by the tool.
- Keep the inputs you used when you need to compare the result with another source or reproduce it later.
Frequently asked questions
Is the calculation sent to a server?
No. The engine runs directly in your browser.
Can I change the values and calculate again?
Yes. Adjust the inputs and run the calculation again immediately.
Why can the result differ from another website?
Two services may use slightly different conventions, astronomical thresholds or historical rules. Check the parameters and assumptions stated by each tool before comparing their results.
Related tools
Keep going with these tools
Tools similar or complementary to this one.
Similar tools
Calculate morning and evening golden and blue hour periods for any location and date.
Dates & timeNewUse this tool
Convert a date and time between two time zones.
Dates & timeNewFeaturedUse this tool
Find overlapping meeting times across two time zones.
Dates & timeNewUse this tool
Read next
GuideBest practicesBeginner
Date and time calculations: a practical guide
Date differences, durations, business days, ISO weeks, recurrences and formats: choose the right date and time calculation.
7 September 20262 min
GuideBest practicesIntermediate
How to calculate business hours between two dates and times
Understand the difference between business days, business hours and working time, then calculate useful time inside opening hours.
8 September 20262 min
GuideBest practicesBeginner
How to calculate work hours with a break
Calculate actual working time between a start and end time, subtract breaks and handle shifts that cross midnight.
8 September 20262 min
GuideBest practicesIntermediate
Time zones and meetings: avoid offset mistakes
Convert times between countries, understand daylight saving time and find international meeting slots without mental arithmetic.
7 September 20262 min