Inspect code copied from a log
Expand a compact block to follow conditions and calls. Remove log prefixes, error messages and Markdown fences before supplying the actual source.
JavaScript formatter
Format JavaScript, TypeScript or JSX for easier reading without executing code. Processing runs locally in your browser.
- Clipboard
- Export
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This input could not be processed. Check its syntax and the limitations explained below.
Result
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How does this tool work?
Reformat JavaScript to make blocks, expressions and statements easier to read. The formatter parses syntax before producing consistent layout instead of splitting on every brace or semicolon. Strings, template literals and regular expressions containing those characters therefore retain their role. Code is processed as local text: functions pasted into the form are never called, and modules mentioned in import statements are not loaded to run your program.
The engine uses a JavaScript syntax parser supporting recognized TypeScript and JSX constructs. It rebuilds layout from that representation, with indented blocks and consistent operator spacing. Quote styles, semicolons and other written forms may be normalized while literal values remain equivalent.
This is not compilation. A TypeScript annotation such as : string stays an annotation, and JSX stays JSX. Output does not automatically run in a browser expecting standard JavaScript. The formatter checks neither types nor imports or variable names; accepted syntax may still contain logic errors.
Supported syntax depends on the bundled parser. Experimental JavaScript proposals, compiler extensions or ambiguous TypeScript/JSX constructions may be rejected. Use the project’s toolchain for specialized syntax rather than treating this form as a replacement for all its options.
Formatting does not minify, rename variables or remove unused code. It produces no source map and does not load your local Prettier configuration. Downloads use a default .js extension: rename TypeScript or JSX output appropriately before adding it to a repository.
How to use this tool
Supply complete source code
Paste relevant statements with closed strings and comments. Importing an accepted file does not run its program.
Run syntax formatting
Inspect indentation. On rejection, look for unfinished strings, missing braces or unsupported specialized syntax.
Review before integration
Check literals, copy or download output and choose the extension matching your source language. Editing the source hides the old result.
Use cases
Discuss a condition during review
Present readable blocks before discussing behavior. Layout does not replace tests for the branches that actually execute.
Prepare readable TypeScript examples
Retain annotations in a teaching example without pretending to compile them. Check the code with TypeScript in its real environment afterward.
Examples
Retain a string, regex and template literal
The ; and {} characters inside literals do not become block boundaries. The TypeScript annotation remains because no JavaScript compilation takes place.
Input
const value: string="a;{b}";const re=/[{};]/g;const t=`x;${value}`;Result
const value: string = "a;{b}";
const re = /[{};]/g;
const t = `x;${value}`;
Expand a conditional block
The condition and a() call remain the same. Spaces, line breaks and block indentation change without executing the condition.
Input
if(x){a();}Result
if (x) {
a();
}
Tips and best practices
- Use original source rather than a minified bundle when you need meaningful names and comments. Layout cannot reconstruct renamed symbols.
- Check type errors using your project’s compiler or language server; this form does not perform type analysis.
- If your team requires specific formatting, apply the repository’s configuration after using this tool for inspection.
- Remove API keys before publishing an excerpt. Local processing avoids uploading them to a formatter, not later disclosure through copied code.
Sources and references
- ECMAScript Language Specification (opens in a new tab), Ecma InternationalPage in English
- The TypeScript Handbook — Everyday Types (opens in a new tab), TypeScriptPage in English
Frequently asked questions
Is my JavaScript executed while formatting?
No. The engine parses and rewrites a syntax representation. It does not call eval or execute functions and imports declared in the text.
Can braces inside strings create false code blocks?
The parser distinguishes strings, templates, regular expressions and code blocks, avoiding blind splitting on characters that belong to a literal.
Are TypeScript and JSX converted into JavaScript?
No. Recognized constructs are retained during layout. Compile with project tools and adjust the downloaded file extension when working with TypeScript or JSX.
Does accepted code have to be correct?
Success only confirms that the parser recognizes the excerpt. Unknown variables, incompatible types, missing imports and business errors need separate analysis and tests.
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