Online HTML Prettify: Format Your Code

Tags packed together can make HTML’s nesting hard to follow. An online HTML prettifier adds whitespace and indentation to lay out the markup.

This article walks through formatting HTML with the tool and checking the result before you copy it.

TL;DR

Online HTML prettify adds line breaks and indentation so you can inspect markup, but it does not validate or repair the document.

• Paste HTML into the input area and choose Prettify HTML.
• Review and copy the formatted result before using it.
• Use an HTML validator separately when you need to check syntax.

What does online HTML prettify do?

An HTML prettifier adds whitespace so you can scan tags and their nesting. CodeForGeek loads js-beautify in the page and calls its HTML formatter with two-space indentation, an 80-character wrap length, and preservation of existing newlines subject to a limit.

The configured options control the formatted text. A formatter may make a missing closing tag simpler to spot, but it does not prove validity or repair structure.

Prettifying lays out markup. Minifying removes whitespace to make a compact file. Use the site’s developer tools directory to find its separate HTML minifier.

Task	What changes	Next check
Prettify	Line breaks and indentation	Review the markup
Validate	Reports markup errors	Fix reported issues
Minify	Removes formatting whitespace	Test the deployed page

How to prettify HTML with this tool

The formatter takes the HTML Input and places the indented version in Formatted Output. Check the result against your source before copying it.

Step 1: Paste your HTML

Copy the markup you want to read and paste it into the HTML Input field. Start with a representative section if the file is large, so you can check how the output handles its elements before formatting the full document.

Step 2: Format the markup

Choose Prettify HTML. The page calls html_beautify() with configured indentation and newline options, then puts the formatted string in Formatted Output.

Step 3: Review and copy the result

Check the tag nesting and compare script, style, comments and whitespace-sensitive text with the source. Then select and copy the output. Clear All empties both fields.

If you need a persistent formatter in an editor rather than a one-off browser tool, CodeForGeek’s VS Code extensions guide discusses Prettier for HTML and other web code. An editor extension can fit a repeated project workflow, while an online formatter is suited to a quick snippet inspection.

What should you check after formatting?

Choose the next check based on what the markup contains. The tool loads its formatter library from jsDelivr, so do not assume it works offline or that pasted source remains only on your device.

Situation	What to check	Safer next step
Markup appears malformed	Check whether tags are paired and nested as intended. Run a dedicated HTML validator to find markup errors. Formatting alone does not validate the document.
Inline script or style is present	Compare its content with the original and test the page	Keep a source copy and review changes before saving
Whitespace carries meaning	Text inside preformatted or whitespace-sensitive content	Compare rendered behavior rather than assuming whitespace is harmless
Source contains secrets or private data	Whether it is appropriate to paste into a web page	Use a local editor or formatter instead

After formatting, preview the page or run project tests, especially for templates and inline code. Check behavior in the browsers you support.

Conclusion

Keep a copy of the source and use the formatter to inspect its layout. Run a validator or tests separately when you need to check correctness.

The js-beautify project documentation explains the library behind this page.

FAQ

These answers distinguish the online tool from editor-specific formatters and syntax checkers.