Code Formatter
Beautify JavaScript, TypeScript, JSON, CSS, HTML, Markdown and more in your browser. Powered by Prettier 3. No upload, no setup, no signup.
Input
Output
A tiny, in-browser Prettier playground
Prettier is the de-facto standard for code formatting in the JavaScript world. It enforces a consistent style across files, languages and contributors so teams stop arguing about spaces and semicolons. FreeLabTools wraps Prettier in a zero-setup web UI: paste your code, pick a language, click Format.
Supported languages
We ship Prettier's official plugins so the output matches what you'd get in any Prettier- configured project:
- JavaScript, TypeScript, JSX / React — modern syntax including ES2024, decorators, optional chaining.
- JSON, JSON5 — compact data, plus the more relaxed JSON5 with comments and trailing commas.
- CSS, SCSS, Less — full stylesheet support with selector grouping.
- HTML — including embedded scripts and styles.
- Markdown — table alignment, list normalization, code fence padding.
- YAML — useful for cleaning Docker, Kubernetes, GitHub Actions configs.
- GraphQL — schema and query formatting.
Performance: why this is fast
Prettier's standalone bundle is small (~85 KB), but each language plugin can be 100-800 KB. Loading them all upfront would slow the first paint. Instead, this page loads plugins on demand: when you pick TypeScript, only the TypeScript plugin downloads. On a typical connection the first format takes about half a second; subsequent ones are instant.
Privacy
Everything runs inside the browser tab — Prettier itself executes locally. Your code is never sent to a server. The only network traffic is the (one-time) download of Prettier's public assets from a CDN.
Use cases
- Quickly clean up a JSON or YAML file before pasting it into a config.
- Fix the indentation of a snippet from a forum or chat.
- Apply your project's style to one-off scripts without installing Node.
- Teach Prettier defaults to new team members.
Frequently Asked Questions
- How does this online code formatter work?
- This tool runs Prettier 3 directly in your browser. Select a language, paste your code, and click Format. Prettier parses your code into an AST and reprints it with consistent style. Language plugins load on demand so the page stays fast.
- Does it upload my code to a server?
- No. Prettier executes entirely inside your browser tab — your code never leaves your device. The only network traffic is the one-time download of Prettier's public JavaScript bundles from a CDN.
- What languages and formats are supported?
- The formatter supports JavaScript, TypeScript, JSX/React, JSON, JSON5, CSS, SCSS, Less, HTML, Markdown, YAML, and GraphQL. These are Prettier's official plugins, so the output matches what you'd get in any Prettier-configured project.
- What are common use cases for this code formatter?
- Use it to quickly clean up JSON or YAML before pasting into a config, fix indentation of code snippets from forums or chat, apply Prettier defaults to one-off scripts without installing Node, or standardize code style before sharing in documentation.
- Is this code formatter really free with no limits?
- Yes, it is completely free. There is no signup, no file-size limit, and no usage cap. You can format as many files as you want. The tool is open and ad-supported — no premium tier exists.