How is this different from Minify on the HTML Formatter page?

This page is a dedicated minifier with three optional steps, a live size display in KB, and a savings percentage. The HTML Formatter’s Minify mode always strips comments and collapses whitespace, has no empty-attribute option, and does not show sizes. Use this page when you want those checkboxes; use the formatter when you also need a beautified copy.

What does each checkbox do?

Remove Comments deletes blocks, but leaves conditional comments that start with <!--[if. Collapse Whitespace turns whitespace between tags into nothing, then collapses runs of two or more spaces or line breaks inside text to a single space, and trims the result. Remove Empty Attributes drops class, id, style, title, or alt when the value is an empty double-quoted string (class="" or id=""). All three options are on by default.

Will whitespace inside pre, script, or style be kept?

Not if Collapse Whitespace is on. Those elements are not special-cased. Several spaces or line breaks inside a or a are reduced to a single space, which can break formatted code or preformatted text. Turn that option off when those regions matter.

Which empty attributes are removed?

Only class, id, style, title, and alt, and only when they are written with empty double quotes. A single-quoted class='' is left alone, and empty attributes with other names are left alone. Values that contain a space are not treated as empty.

Is my HTML sent to a server?

No. Minification runs in your browser as you type. Closing the tab discards what you pasted. Do not paste pages that contain secrets or private user data if you would not be comfortable with them sitting in memory on this device.

Is there a file size limit?

There is no server-imposed limit, because nothing is uploaded. A few thousand lines is comfortable. A large exported page can make the tab feel slow; in that case, minify a smaller fragment or use a local tool.

HTML Minifier Online

Minify HTML by removing comments, collapsing whitespace, and stripping empty attributes.

Remove CommentsCollapse WhitespaceRemove Empty Attributes

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