How this tool works
Splits the pasted markup into tags, comments and text, then places each on its own line with indentation that follows the nesting depth. Void elements such as img, br and meta do not increase the depth.
How to use it
- Paste the HTML you want to read or clean up.
- Run the formatter.
- Review the indented output and compare it with the original.
- Copy the result into your editor and test it in staging before publishing.
Limits to keep in mind
It is a lightweight formatter, not a full HTML parser or validator. Whitespace-sensitive content such as pre blocks, inline scripts and inline text flow can look different after formatting, so compare the result with the original before replacing live files.
Frequently asked questions
Does the formatter run my scripts?
No. The input is handled as plain text in your browser. Scripts are not executed and referenced files are not fetched.
Will formatting change how my page looks?
It should not for most pages, but extra whitespace can matter in inline text, pre blocks and some layouts. Always compare and test before publishing.
Does it fix invalid HTML?
No. It only re-indents what you paste. Use the HTML Structure Checker to look for common problems.
Formatting for readability
HTML is often delivered as one long line, or as a block with inconsistent spacing, because build tools, page builders and plugins do not care how the source looks. That is fine for browsers, but it is hard for people. The HTML Formatter takes the markup you paste and places tags and text on separate, indented lines so the structure is easier to scan.
The tool treats your input as plain text. It does not execute scripts, load stylesheets, request images or fetch any referenced file. It reads the text, breaks it into tags, comments and text, and rebuilds it with indentation that shows which elements are nested inside others. The result is the same markup, laid out so you can see parent and child elements at a glance.
When formatting helps
Formatting is useful whenever you have to read code that you did not write or that has been compressed. Examples include checking a snippet from an email template, reviewing the output of a page builder, finding a missing closing tag, comparing two versions of a section, or preparing code to be pasted into documentation or a support ticket.
It is also a good first step before editing. When you can see the nesting, you can find the right element to change and avoid breaking the structure around it. For teams, consistent formatting makes code reviews and version history easier to follow, because changes show up as real differences and not as noise from spacing. For simple one-off tasks, a web-based formatter saves you from installing an editor extension.
Preserve behavior and meaning
Whitespace in HTML is not always harmless. Browsers collapse most spaces and line breaks, so adding indentation between block elements normally changes nothing visible. But in some places whitespace matters. Inside preformatted text, text areas and code blocks, line breaks and spaces are displayed exactly as written. Between inline elements such as links, spans and images, a space or a line break can appear as a visible gap.
Because this formatter is lightweight and is not a full HTML parser, it can change the whitespace in these sensitive places. After formatting, look at inline text, pre elements, textareas and scripts, and compare them with the original. If a block looks different, restore it by hand. Never assume that nicely indented code is identical in effect to the original.
Use a careful review workflow
Work on a copy, not on the only version of the file. Paste the HTML into the editor, run the formatter, and read the output before you use it. Check scripts, style blocks, comments, conditional comments and preformatted text, which are the areas most likely to be affected.
If you plan to replace production code, test the formatted version in a staging environment or a local browser first, and compare how the page looks and behaves. Keep the original until you have confirmed that nothing changed. For large projects, the better long-term answer is a formatter built into your editor or build pipeline, with rules that your whole team shares. This online tool is ideal for quick jobs and for code that lives outside such a pipeline.
What the formatter does not do
It does not validate your markup. A formatter can lay out invalid HTML as neatly as valid HTML, and it will not warn you about unclosed tags, wrong nesting, missing attributes or deprecated elements. To check correctness, use a validator such as the W3C Markup Validation Service, or the HTML Structure Checker on this site for common issues.
It also does not fix errors, improve accessibility, optimize performance or change the meaning of your code. It does not know about your framework, templating language or CMS syntax. If your file contains template tags, such as PHP, curly-brace expressions or server includes, the tool treats them as text, so the result may look unusual around those areas. Check these parts with extra care.
Troubleshooting odd output
If the output looks wrong, there are a few common causes. Unclosed or mismatched tags can make the indentation drift further to the right as the formatter tries to nest everything. Look for the point where the indentation starts to increase and find the missing closing tag just before it.
Text that contains angle brackets, such as comparisons in inline scripts or code samples that are not properly escaped, can be mistaken for tags. Template code can do the same. For very large files, the browser may be slow, so paste a smaller section. If the formatter changes something important, restore that part from your original. When in doubt, compare the two versions side by side with a text comparison tool to see exactly what changed.
Privacy and safe handling
The formatting runs in your browser. The tool does not send your pasted code to a server, and it does not store it. Even so, treat any web page with care when you handle sensitive material. Remove API keys, passwords, tokens, private URLs and personal data from your snippet before pasting it into any online tool, and share only what you need.
If your code belongs to a client, check what your agreement allows before you paste it anywhere. For confidential or regulated work, use a formatter inside your own development environment. After formatting, copy the output into your project and double-check it. A few minutes of review costs little and prevents small formatting changes from becoming unexpected bugs.
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