HTML Minifier — Compress HTML Online for Smaller Page Size
Minify HTML by removing comments, collapsing whitespace, and stripping optional attribute quotes and void-element slashes. Reports byte savings. Preserves IE conditional comments and preformatted <pre> / <textarea> / <script> / <style> content. 100% local.
Last updated:
Original
394 B
Minified
302 B
Saved
23%
Need to go the other way? HTML Beautify →
Paste HTML to strip comments, collapse whitespace, and remove optional slashes. Reports byte savings side-by-side with the original size. Preserves IE conditional comments and the contents of <pre>, <textarea>, <script>, and <style> so functionality and layout stay intact.
What is HTML Minifier?
HTML minification is the process of removing every byte from a page that doesn't affect what the browser renders. That means stripping HTML comments (except conditional comments), collapsing runs of whitespace to a single space (or nothing between block-level tags), removing optional attribute quotes when values are unambiguous, and eliminating the self-closing slash on void elements like <br /> and <img />. On modern sites, HTML minification typically saves 15–35% on hand-written pages and 40%+ on framework-generated output — savings that add up quickly when combined with gzip / brotli compression, cache-friendly headers, and modern CDN delivery. Every major static site generator (Astro, Next.js, Hugo, Eleventy) minifies HTML in production; this tool lets you inspect exactly what a minifier would output before wiring one into your build pipeline.
How to minify HTML online
- 1Paste your HTML into the input pane.
- 2Adjust options: remove comments (default on), collapse whitespace (default on), remove void-element slashes (default on), remove attribute quotes (opt-in — more aggressive).
- 3The output pane shows the minified HTML; the header reports original size, minified size, and % saved.
- 4Copy the output and use it as your build artifact — or wire this same logic into your pipeline.
Use Cases
Shrink static site output
Even after Astro / Next.js pre-render, generated HTML often has extra newlines and indentation. Minify to shave 10–30% off first paint.
Inline HTML in email templates
Email clients strip line breaks unpredictably and don't gzip. Pre-minified HTML avoids surprises.
Embed HTML in a single-line context
When embedding HTML in a JSON string / SQL insert / Markdown code fence, minifying first removes accidental line breaks that would need escaping.
See what a production build produces
Before shipping, run your source template through this tool to sanity-check that minification doesn't break your layout — especially around <pre> / <textarea>.
Key Concepts
- Void element
- An HTML element that cannot have content and doesn't need a closing tag: area, base, br, col, embed, hr, img, input, link, meta, param, source, track, wbr. The self-closing slash <br /> is optional in HTML5.
- Preformatted element
- Elements whose whitespace is preserved by the browser: <pre>, <textarea>, and (functionally) <script> and <style>. Minifiers must leave their contents alone.
Tips & Best Practices
- ▸Never minify inside <pre>, <textarea>, <script>, or <style> — whitespace inside those is meaningful. This tool preserves them automatically.
- ▸Keep IE conditional comments (<!--[if IE]> ... <![endif]-->) — they're meaningful markup for legacy IE support, not just comments.
- ▸'Remove attribute quotes' is the most aggressive option — it saves a few bytes per attribute but reduces readability. Skip it unless every byte matters.
- ▸For maximum production savings, combine minification with gzip / brotli on the wire — order-of-magnitude effects, not additive.
Frequently Asked Questions
What does the minifier remove?
By default: HTML comments (except IE conditional comments), redundant whitespace between tags, and optional self-closing slashes on void elements (<br/> → <br>). You can also opt in to attribute-quote stripping when the value is unambiguous.
Does it preserve <pre>, <textarea>, and <script> content?
Yes. Any content inside <pre>, <textarea>, <script>, or <style> is preserved byte-for-byte — collapsing whitespace inside those would break rendering / functionality.
How much can I save?
Typical hand-written HTML shrinks by 15–35%. Framework-generated HTML with lots of indentation and comments can shrink by 40%+. Combined with gzip / brotli, minification usually adds another 3–8% on the wire.
Are IE conditional comments preserved?
Yes. Any comment matching <!--[if ...]> ... <![endif]--> is kept intact — these are meaningful markup, not just documentation.
Is my HTML uploaded anywhere?
No. Minification runs entirely in your browser.
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