Format JavaScript using Prettier with indentation, quotes, semicolons, width and trailing-comma controls.
LOCAL FILE CONVERSION
Format JavaScript using Prettier with indentation, quotes, semicolons, width and trailing-comma controls.
Drop one UTF-8 source file · Up to 200 KB · No uploadLOCAL INPUT
2 lines · 75 characters · 75 bytes
COMPUTED RESULT
0 output bytes ·
Prettier standalone parses JavaScript with Babel and prints with ESTree. Source is never executed. Comments may be repositioned and formatting is not a security audit, type checker or minifier. TypeScript syntax is outside this JavaScript parser mode.
Processing uses your browser memory. Inputs are not included in page analytics. Text tools accept up to 200,000 UTF-8 bytes unless a tighter limit is stated. Worker operations time out after 45 seconds and can be cancelled. Clipboard and downloads require an explicit action.
Enter your values locally; no inputs are uploaded.
Check validation feedback before reviewing the browser-generated result.
Review the explanation, copy supported outputs or reset the workspace.
Prettier standalone with Babel and ESTree parses and prints JavaScript locally. It supports modern JavaScript syntax accepted by that parser but does not act as a TypeScript type checker.
Prettier standalone parses JavaScript with Babel and prints with ESTree. Source is never executed. Comments may be repositioned and formatting is not a security audit, type checker or minifier. TypeScript syntax is outside this JavaScript parser mode.
Processing takes place locally in browser memory. Inputs are not sent to a processing service, persisted by this tool or included in analytics. Ordinary page requests may still be logged. Clipboard and downloads require explicit actions.
Prettier standalone with Babel and ESTree parses and prints JavaScript locally. It supports modern JavaScript syntax accepted by that parser but does not act as a TypeScript type checker.
No. The source is parsed as data in a disposable Worker. Formatting does not run functions, imports or expressions from the submitted program.
Choose two or four spaces or tabs, semicolon preference, single-quote preference, print width from 40 to 160 and trailing commas all, es5 or none. Prettier determines final layout.
Comments are retained by the formatter where supported but can be repositioned or restyled. Formatting is not byte-for-byte preservation or a formal semantic equivalence proof.
A parser must understand the syntax before printing it. Invalid syntax produces a controlled diagnostic with location information where available; no guessed repair is returned as a valid result.
No. Formatting improves layout. It does not optimize program size, find every correctness issue, check types or certify source security. A related JavaScript Minifier is available separately.