HTML Formatter

Use the html formatter tool online for quick developer workflows. Add examples, caveats, and avoid pasting sensitive secrets.

Free online file converter tool. Works in Chrome Firefox Safari Edge Opera and other modern browsers on Windows macOS Linux Android and iOS. No software installation required. Browser-side processing keeps your file local when supported. Completely free to use with no account needed.

HTML Formatter

Beautify and format HTML code with custom indentation, instantly in your browser.

HTML Formatter Features

Fast, private HTML formatting directly in your browser.

Smart Indentation

Correctly handles block vs inline elements, void tags, and nesting depth.

Instant Results

Format any size HTML snippet instantly. No waiting, no server round-trip.

Browser-Based

Your HTML stays on your device. Privacy-aware, no sign-up needed.

How to Format HTML Online

  1. Paste your HTML

    Drop minified, copied, or machine-generated HTML into the input area on the left. Full documents and loose fragments both work, and no doctype is required. All processing runs in your browser, so the markup stays on your device.

  2. Pick your indent style

    Use the Indent dropdown to choose 2 spaces, 4 spaces, or a tab character. Each level of nesting is offset using that unit, while inline tags such as span, a, strong, and em stay on the same line as their text instead of being pushed down a level.

  3. Format, review, and copy

    Click Format HTML to produce indented, line-broken output on the right. A status line confirms success. Use the Copy button to send the result to your clipboard, or Clear to reset both panes and start over.

How Different Tag Types Are Handled

The formatter classifies each tag before deciding whether to increase the indent level. Block elements open a new nesting level, while inline, void, and self-closing tags stay flat. This table shows how the common cases behave.

Tag typeExamplesAdds indent levelBehavior
Block elementdiv, section, ul, table, pYesChildren are indented one level deeper under the open tag.
Inline elementspan, a, strong, em, codeNoKept on the same line as surrounding content, not pushed deeper.
Void elementbr, img, input, meta, link, hrNoWritten on its own line with no expected closing tag.
Self-closing tagSVG nodes ending in />NoTreated as complete, so no extra closing indent is added.
Text and template syntaxplain text, {{ }}, NoPreserved as-is at the current level; only HTML tags drive indentation.
Embedded script or stylescript, style blocksYes (tag only)Tags are indented but the JS or CSS inside is left untouched.

When to Use the HTML Formatter

Reading minified markup

When you paste a single unreadable line from a build output or a copied page, formatting adds line breaks and indentation so you can follow the document structure at a glance.

Debugging nesting issues

Indentation makes mismatched or misplaced tags obvious. Seeing each level offset helps you spot where a container was left open or closed in the wrong place.

Cleaning generated HTML

Output from CMS editors, email builders, and exporters is often inconsistent. The formatter normalizes indentation to your chosen 2-space, 4-space, or tab convention.

Working with private templates

Because formatting happens entirely in the browser, you can tidy proprietary templates or internal tooling markup without sending anything to a server.

Common Problems and Fixes

Embedded CSS or JavaScript is not indented

This is expected. The formatter indents the script and style tags but preserves their contents exactly as written. To reformat the inner code, use a dedicated JavaScript or CSS formatter on those blocks separately.

Output looks wrong with unclosed tags

The indenter assumes well-formed markup. A missing closing tag can shift everything below it deeper than expected. Close the open element in your source, then format again to restore correct nesting.

Template tags broke the layout

Tags like {{ value }} or PHP blocks are treated as plain text, not HTML, so they sit at the current level instead of opening a new one. The surrounding HTML still formats correctly around them.

Nothing happens after pasting

You must click the Format HTML button to run the tool; it does not format on paste. If the input is empty or only whitespace, the output stays blank. Add content and click the button again.

References

  1. HTML Living Standard - WHATWG
  2. HTML - MDN Web Docs, Mozilla
  3. HTML getting started (indentation) - MDN Web Docs, Mozilla
  4. Pretty-printing - overview
  5. DOMParser - MDN Web Docs, Mozilla
  6. Clipboard.writeText() - MDN Web Docs, Mozilla
  7. HTML elements reference - MDN Web Docs, Mozilla
  8. Blob - MDN Web Docs, Mozilla