Why did tags I never wrote appear in the output?

HTML lets you omit closing tags for elements like li, p, td and option, and a tree-based formatter has to decide where those elements really end. It closes them the same way a browser does and then writes the closing tag out explicitly, so a list written with bare li tags comes back with matching /li tags. The rendered result is identical; the byte count is not.

What happens to a stray closing tag?

A closing tag with no matching open element is dropped, and the number dropped is reported above the output.

HTML Formatter

No upload · runs in your browser

Indent

HTML in

0 characters

Result

Runs entirely in your browser, nothing is uploaded.

How it works

HTML Formatter : Beautify or Minify Markup

Indent HTML into a readable tree or minify it. script, style, pre and textarea are copied through byte for byte, and omitted end tags come back explicit.

What this does

Beautify from a parsed tag tree, indenting with two spaces, four spaces or a tab
An element whose children are all inline stays on one line, so spacing never shifts
script, style, pre and textarea contents are copied through byte for byte
Minify drops comments except conditional  blocks and ones opening <!--!
Counts elements and nesting depth, and warns you when it closed a tag you had left open

FAQ

Almost never, because whitespace is only reflowed where HTML already collapses it. An element whose children are all inline is kept on a single line, and script, style, pre and textarea are copied out verbatim. The one thing to know is that if you apply white-space: pre or pre-wrap to an ordinary element with CSS, the formatter cannot see that rule and will collapse its runs of spaces.

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