HTML Beautifier - Free Online Tool

HTML Beautifier formats minified, copy-pasted, or auto-generated HTML into properly indented, readable markup so you can scan structure, debug nesting issues, and review templates without squinting.

Beautify HTML

Indent size (spaces)

HTML input

Beautified HTML

What is HTML Beautifier?

HTML Beautifier is a free, browser-based tool that takes any HTML string — whether it arrives as a single long line from a minifier, a build pipeline, or a copy-pasted view-source dump — and rewrites it with consistent indentation, one element per line, and predictable spacing around attributes. The output keeps every character of the original markup; only whitespace between tags is adjusted so the document tree becomes visible.

HTML Beautifier handles the cases that simple regex formatters get wrong: comments are preserved on their own lines, DOCTYPE declarations stay at the top, void elements like <br>, <img>, and <input> are emitted without a closing tag, and the raw text inside <script>, <style>, <pre>, and <textarea> is left untouched so you do not silently break templates. Indentation is configurable from 0 to 8 spaces so the output matches whatever your team has agreed in EditorConfig or Prettier.

Typical users are frontend developers reviewing emails or transactional templates, designers inspecting marketing landing pages, QA engineers comparing rendered output to expected markup, and content authors making sense of HTML pasted from a CMS. Because HTML Beautifier runs entirely on your device, no markup is sent to a server — which is important when the HTML in question contains internal product names, customer data, or unreleased designs.

How to Use This HTML Beautifier

Paste your minified or messy HTML into the input textarea. The tool accepts entire documents starting with a DOCTYPE as well as fragments such as a single component or a snippet copied from a Slack message.
Pick an indent size. Two spaces is the most common default; pick four if your team uses 4-space indentation, or zero if you only want one-tag-per-line output with no leading whitespace.
Click Beautify. HTML Beautifier walks the markup, classifies each token as a tag, comment, text node, or raw section, and emits the result with consistent indentation and line breaks.
Read the output in the lower textarea. Each opening tag, closing tag, and text node sits on its own indented line, which makes nesting and structure visible at a glance.
Click Copy to move the formatted markup to your clipboard, then paste it back into your editor, pull request comment, or design review document.
Use Clear when you are ready to format a different snippet. The input, output, and error states reset together so you do not mix two unrelated documents in the same buffer.
If you need a single-line version for embedding in a JSON string or a build artifact, run the formatted output through the HTML Minifier tool linked in the related tools list.

Why Use This HTML Beautifier?

Restores readable indentation to minified HTML so developers can quickly understand template structure without manually inserting line breaks.
Preserves comments, DOCTYPE, and raw content inside <script>, <style>, <pre>, and <textarea> so beautifying never silently breaks templates.
Lets you pick the indent size to match your project style guide, EditorConfig settings, or whatever the rest of your codebase already uses.
Runs locally in your browser, which means proprietary templates and customer-facing markup never leave your device for the formatting pass.
Helps reviewers compare two HTML snippets line by line — beautified output diffs cleanly in pull requests, design QA, and code review tools.
Pairs with the HTML Minifier on the same site so you can switch between human-readable and production-ready markup in a single workflow.

When to Use HTML Beautifier

Inspecting markup pasted from "View Source" of a production page to understand its structure before recreating it locally.
Reviewing transactional email HTML produced by template builders, which is usually emitted as one long line with no indentation.
Debugging WYSIWYG output from a CMS that emits inconsistent whitespace and broken indentation around inline elements.
Preparing an HTML snippet for documentation or a blog post where readers benefit from properly indented examples.
Comparing the output of two template engines side by side after beautifying both with the same indent size for a fair diff.
Cleaning up auto-generated markup from old WordPress, Shopify, or HubSpot pages before migrating it to a new component library.

HTML Beautifier Features

Token-aware formatting

HTML Beautifier classifies the document into tags, comments, text, DOCTYPE, CDATA, and raw sections before printing, which means it produces correct indentation even when input is malformed.

Preserves raw content

Content inside <script>, <style>, <pre>, and <textarea> is emitted exactly as written. The tool only re-indents the surrounding HTML, so embedded code and pre-formatted text remain untouched.

Void element awareness

Tags like <br>, <hr>, <img>, <input>, <meta>, and <link> are emitted without a closing tag, matching the HTML5 specification rather than forcing XML-style self-closing on them.

Configurable indent size

Choose 0 to 8 spaces of indent. Most teams settle on 2 or 4; the option exists so HTML Beautifier output matches whatever Prettier, EditorConfig, or your CMS already enforces.

One-click copy and clear

A dedicated Copy button moves the beautified markup to your clipboard, while Clear resets input, output, and error states so the page is ready for the next snippet.

Local-only processing

All beautification happens in your browser. Your markup is never uploaded, so internal templates, prelaunch designs, and customer-facing HTML stay private during formatting.

How HTML beautification preserves semantics while restoring readability

HTML is a tree of nested elements punctuated by text nodes, comments, and a small set of raw-text sections. A correct beautifier has to distinguish all of these because each one has different whitespace rules. For example, the space inside a paragraph is significant — collapsing it the wrong way changes how the browser renders the text — while the whitespace between block-level tags is purely cosmetic.

HTML Beautifier handles this by tokenizing the input first and only reformatting whitespace at safe boundaries. Tags get indented to reflect nesting depth, comments are placed on their own lines, and raw-text elements like <pre>, <textarea>, <script>, and <style> are passed through unchanged. The result is a document that looks dramatically more readable while rendering identically in any compliant browser.

Void elements are a common stumbling block for naive formatters. The HTML5 spec defines a fixed list of elements (such as <br>, <img>, and <input>) that cannot have closing tags. HTML Beautifier recognises these and emits them as a single self-contained line, which keeps your indentation correct and avoids inventing closing tags that would not parse.

Decision Guide

Best for

Developers reviewing minified or auto-generated HTML.
Teams comparing template output across engines or releases.
Anyone copying markup from a CMS, email builder, or production page.

Avoid when

You need to validate or repair broken HTML — beautifying does not fix structural errors.
You want to reformat JavaScript or CSS embedded inside the HTML; use the dedicated beautifier tools instead.

Example

Beautify a minified snippet

Input

<div><h1>Hi</h1><p>Hello <b>world</b></p></div>

Output

<div>
  <h1>Hi</h1>
  <p>Hello <b>world</b></p>
</div>

HTML Beautifier Best Practices

Match the indent size to your project

If your repo uses 2-space indentation everywhere else, set HTML Beautifier to 2 as well. Consistent indentation across HTML, CSS, and JS makes the whole codebase easier to scan and reduces noise in code review diffs.

Beautify before reviewing diffs

When two templates differ only in whitespace, beautifying both first turns the diff into a meaningful comparison of structure rather than line-break noise. This is especially useful when migrating between template engines.

Re-minify before production

HTML Beautifier output is for human readers, not for production traffic. Once you are done reviewing or editing, run the result through HTML Minifier so your real users still get the smallest possible payload.

Do not edit raw text by hand

If <script> or <style> content needs to change, edit it as JavaScript or CSS — not as HTML. HTML Beautifier preserves those sections verbatim, so any reformatting you want inside them belongs in the JavaScript or CSS beautifier instead.

Validate before beautifying

A beautifier cannot fix structural errors like unclosed tags or stray angle brackets; it can only reformat what you give it. If the output looks off, run the source through an HTML validator first so the tree you are formatting is well-formed.

Troubleshooting

Output is missing line breaks inside <pre> or <textarea>.

That is intentional. HTML Beautifier preserves raw text inside <pre>, <textarea>, <script>, and <style> to avoid changing how the page renders.

The tool says "Enter HTML to beautify."

Paste at least one tag or character into the input textarea, then click Beautify again.

Common HTML readability problems HTML Beautifier solves

Production HTML arrives on a single line

Build pipelines minify HTML to save bytes, which removes every newline and indent. HTML Beautifier reverses that compression so you can read structure again before debugging or extending the template.

CMS output mixes inline and block formatting

Rich-text editors often emit erratic whitespace around inline elements, making it hard to spot real structural problems. Beautifying produces a predictable layout where every block tag starts on its own line.

Pasted markup is missing visible structure

When you copy a snippet from a Slack message or a forum, formatting often collapses into one paragraph. HTML Beautifier rebuilds the tree visually so you can decide what to keep and what to remove.

Code review diffs are unreadable

Beautifying both sides of a diff before review lets reviewers compare semantic changes instead of whitespace noise, which speeds up approval and reduces back-and-forth.

Documentation examples look cramped

HTML examples in docs and blog posts read more clearly when properly indented. Beautifying lets you publish examples that match the style of the surrounding code without manual formatting.

FAQs

Does HTML Beautifier change the meaning of my HTML?

No. HTML Beautifier only changes whitespace between tags and the indentation of each line. The document tree, attributes, text content, and raw sections (such as script and style) are preserved exactly, so the beautified output renders the same as the original in every browser.

What happens to comments and DOCTYPE?

Comments are kept on their own lines at the depth they appeared, and the DOCTYPE is emitted at the top of the document. Nothing is removed, so the output remains a faithful representation of the original markup.

Will the beautifier reformat my JavaScript or CSS?

No. Content inside <script> and <style> blocks is passed through unchanged. If you want to format the embedded code, use the JavaScript Beautifier or CSS Beautifier tools and then paste the reformatted code back into the HTML.

What indent size should I pick?

Match whatever the rest of your project uses. Most modern codebases use 2 spaces; older codebases and some style guides prefer 4. HTML Beautifier supports any value from 0 to 8 so it can fit into existing conventions without manual edits.

Is the tool safe for confidential markup?

Yes. All processing happens locally in your browser. Your markup is never sent to a server, so internal templates, prelaunch designs, and customer-facing pages can be beautified without leaving the device.

Why does my output still have one long line inside a <pre> block?

Because <pre> preserves whitespace literally. HTML Beautifier intentionally leaves that content alone so the rendered page continues to look exactly as the author intended. If you want to reformat that text, edit it directly rather than relying on the beautifier.

Can I undo a beautify by running HTML Minifier on the output?

Yes. HTML Beautifier and HTML Minifier are designed as a pair. Beautifying restores readability for humans, and minifying compresses the result for production. Round-tripping through both tools is safe as long as you start with valid HTML.

Does HTML Beautifier fix broken or invalid markup?

No. The tool reformats whitespace but does not repair missing closing tags, stray angle brackets, or unbalanced quotes. If the input is malformed, validate it with a tool like the W3C validator first and fix the structural problems before beautifying.

HTML Beautifier is the fastest way to turn a wall of minified markup back into a tree you can read, review, and extend — privately, in your browser, with no signup.

HTML Minifier

Live

Strip comments and collapse whitespace to shrink HTML payload size.

CSS Beautifier

Live

Format and indent minified CSS into readable style sheets.

JavaScript Beautifier

Live

Format and indent minified JavaScript for reading, auditing, and debugging.

HTML Encode

Live

Escape HTML special characters to safe entities.