When HTML whitespace matters and when it does not
HTML is generally tolerant of formatting whitespace, but some elements and embedded languages make blind minification risky.
Whitespace between ordinary block elements is often…
Whitespace between ordinary block elements is often only for source readability. Whitespace inside preformatted content and some inline layouts can be visible to users.
HTML attributes, inline CSS, and JavaScript have…
HTML attributes, inline CSS, and JavaScript have their own parsing rules. A text replacement cannot safely replace a standards-aware build tool for every document.
Compare rendered output and run your normal…
Compare rendered output and run your normal validation after minification. Smaller source is not useful if it changes layout, accessibility, or script behavior.
Use the related tool carefully
This guide is paired with a browser-only utility. The tool is a practical aid for small examples and inspection; it is not a substitute for application testing, a formal data pipeline, or professional review where the decision has higher consequences.
Open the related HTML Minifier