You Might Also Like
HTML Formatter Online — Free HTML Beautifier & Code Prettifier
About this tool
What Is This HTML Formatter?
This is a free, browser-based HTML formatter and beautifier that takes raw, minified, or inconsistently indented HTML markup and restructures it with clean, readable 2-space indentation. It handles the full range of real-world HTML — properly nested block and inline elements, void elements like br, img, input, meta, and link that should not receive a closing indentation step, self-closing tags ending with />, DOCTYPE declarations, HTML comments, and deeply nested component trees. Everything runs entirely inside your browser tab using JavaScript. No code is ever sent to a server, stored in a database, or logged anywhere.
What makes this formatter stand out is full inline formatting support for embedded CSS and JavaScript. Standard HTML formatters only indent the tags — they leave the contents of style and script blocks as untouched raw text. This tool goes further: it detects every style block and applies CSS-specific formatting to it (rule blocks, property lists, selector grouping), and it detects every script block and applies brace-based JavaScript indentation. The result is a single-pass formatter that produces a completely clean, end-to-end readable HTML document — not just a slightly-less-messy one.
HTML formatting is a frequent daily need for front-end developers, designers, and anyone who works with web content. Minified HTML arrives from build tools, CDN responses, email service providers, CMS systems, web scrapers, and API payloads. Copy-pasted template fragments from documentation, Stack Overflow, or AI tools often arrive with inconsistent or missing indentation. Even hand-written HTML in editors without auto-formatting can accumulate structural inconsistencies over time. A formatter resolves all of these situations in under a second — paste or upload, click Format, and you have a clean, readable document ready for debugging, code review, or committing to source control.
The formatter also includes a history bar that saves up to 15 timestamped snapshots of every formatting session. If you format a document, make some edits, format it again, and then want to compare the two states side-by-side, the history chips let you restore any previous version instantly — no undo limit, no lost work. A live line-number gutter stays synchronized with the editor as you scroll, making it easy to reference specific lines when discussing code in a review or bug report.
Features
- Formats HTML with consistent 2-space indentation and correct tag nesting depth
- Automatically prettifies inline <style> CSS blocks — rule blocks, properties, and selectors
- Automatically prettifies inline <script> JavaScript blocks — brace-indented, readable JS
- Live line-number gutter synced to editor scroll — updates instantly as you type or format
- History bar — up to 15 timestamped snapshots, click any chip to restore that version
- File upload and drag-and-drop — load .html or .htm files without copy-pasting
- Download button — save the formatted result as an .html file to your computer
- Handles void elements (br, img, input, meta, link, hr, etc.) with no extra indent step
- Handles self-closing tags (/>), DOCTYPE declarations, and HTML comment blocks
- Works on partial HTML fragments — no complete document required, any snippet works
- One-click Copy button copies the full formatted output to clipboard
- 100% client-side — no data sent to any server, no sign-up, no watermark, no limit
How to Use
Paste your raw, minified, or unformatted HTML directly into the left editor panel. You can also click the Upload button to load an .html file from your computer, or drag and drop a file directly onto the editor area. The editor accepts full HTML documents, partial fragments, component templates, email HTML, and any other valid or near-valid HTML content.
Click the Format button to run the formatter. The output appears immediately in the right panel with 2-space indentation, properly nested tags, and formatted inline CSS and JavaScript. If your HTML contains a style block, its contents are formatted as CSS with correctly indented rule blocks and property lists. If it contains a script block, its contents are formatted as JavaScript with brace-based indentation. Void elements — br, img, input, meta, link, hr, area, base, col, embed, param, source, track, wbr — are never given an extra indentation step, so they sit cleanly on their own lines without causing incorrect nesting downstream.
Use the line-number gutter on the left side of both panels to reference specific line numbers when filing bug reports, discussing code in pull request reviews, or identifying the source of a structural problem. Line numbers update live as you type and stay in sync with editor scroll position.
Every time you click Format, the current output is automatically added to the History bar at the bottom of the screen with a timestamp. If you format a document multiple times with different edits between passes, all versions are saved. Click any history chip to restore that version of the formatted output instantly. Up to 15 history entries are kept per session.
Click Download to save the formatted HTML as a file. The filename is derived from any uploaded file's original name, or defaults to formatted.html for pasted content. Click Copy in the top toolbar to copy the entire formatted output to your clipboard in one click — ready to paste into your code editor, IDE, or source control commit.
For minified HTML from a build tool or CDN — paste it in and hit Format. The entire document will be expanded from a single line into a fully readable, indented structure. For HTML received from a web scraper or API — paste the raw response, format it, then use the line numbers to navigate to specific elements for debugging. For email templates — paste the HTML from your email service provider's export, format it, and inspect the table nesting structure that email clients require.
Common Use Cases
Frequently Asked Questions
An HTML formatter takes minified, compressed, or inconsistently indented HTML and restructures it with consistent indentation so every element is easy to read. It handles nested tags by incrementing indentation depth at each opening tag and decrementing it at each closing tag. It correctly handles void elements (br, img, input, meta, link) that should not increase indentation depth, self-closing tags ending with />, DOCTYPE declarations, and HTML comment blocks. The result is a clean, navigable document that matches the structure expected by modern code style guides.
Yes — this is one of the key features that separates this formatter from basic HTML indenters. When the formatter encounters a style block, it applies full CSS formatting to its contents: each rule block is placed on its own line, properties are indented inside rule blocks, and selectors are properly spaced. When it encounters a script block, it applies brace-based JavaScript indentation so function bodies, if blocks, and loops are all correctly nested. Most online HTML formatters skip this step and leave inline CSS and JS as unformatted text — this one formats the entire document end-to-end.
Yes. You do not need a complete HTML document with a doctype, html, head, and body. Paste any fragment — a single div and its children, a navigation component, a form, a table, or a React/Vue/Angular template — and the formatter indents it correctly. The formatter works on whatever structure is present in the input, not on assumptions about what a complete document should look like.
Every time you click Format, the formatted output is automatically saved to the history bar as a timestamped chip. Up to 15 history entries are saved per browser session. Click any chip to instantly restore that version of the formatted HTML — useful for comparing different formatting passes, recovering from accidental edits, or switching between multiple documents you were working on in sequence. History is stored in memory for the current session only and is not persisted to localStorage or any server.
Void elements in HTML — br, img, input, meta, link, hr, area, base, col, embed, param, source, track, and wbr — do not have closing tags and should not cause a change in indentation depth. The formatter recognizes all standard void elements and handles them correctly: they sit at the current indentation level without pushing subsequent elements one level deeper. Self-closing tags written with a trailing slash (like <br /> or <img src="..." />) are also handled correctly and treated equivalently to their non-self-closing counterparts.
No. All formatting runs entirely in your browser using JavaScript. Your HTML is never transmitted over the network, never stored on any server, and never logged. This makes the tool safe to use with internal templates, proprietary component code, client work, and any HTML that you would prefer not to share with a third-party service. The tool works fully offline once the page is loaded.
The formatter uses 2-space indentation, which is the most widely adopted standard for HTML, CSS, and JavaScript in modern front-end codebases. This matches the default settings of Prettier, the most popular code formatter in the JavaScript ecosystem, and aligns with the HTML style guides published by Google, Airbnb, and most major organizations. Two spaces keep nested structures compact and readable without the wider visual spread of 4-space or tab-based indentation.
Yes. Click the Upload button in the toolbar to open a file picker and select any .html or .htm file from your computer. You can also drag and drop a file directly onto the editor area. The file contents load into the editor and you can then click Format to prettify them. After formatting, click Download to save the result back to your computer as a .html file — useful for batch-formatting template files or cleaning up downloaded web pages.
The formatter handles many common real-world HTML imperfections: missing closing tags on non-void elements, attributes without quotes, mixed case tag names, and unclosed comments. It applies best-effort indentation based on the tag structure it can detect. Very severely malformed HTML — like deeply mismatched tag hierarchies — may produce unexpected indentation, but the output will still be syntactically indented rather than flat. For production code, consider also validating your HTML with the W3C Markup Validator after formatting.
There is no hard size limit imposed by the tool — it is bounded only by your browser's available memory. In practice, formatting HTML files up to several megabytes works smoothly. For very large files (5 MB+), formatting may take a moment on older or lower-powered devices. If you are working with extremely large generated HTML (such as a full static site export), consider splitting it into sections or using a local formatter like Prettier via the command line for better performance.