HTML FORMATTER & BEAUTIFIER
FORMAT · BEAUTIFY · MINIFY · VALIDATE HTML CODE INSTANTLY
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FORMATTED OUTPUT
Input: 0 chars Output: 0 chars 0 lines 0 tags

Free HTML Formatter & Beautifier – Format HTML Code Online

By RapidTool Team  ·  Last updated: September 2026

Our free HTML formatter instantly beautifies messy, minified, or unformatted HTML code. Whether you're working with raw HTML files, template output, or copied webpage source code, our tool adds proper indentation, formats nested elements, and makes your code readable — in seconds.

Features

⚡Instant formatting with customizable indentation (spaces or tabs)
🗜️Minify HTML to reduce file size for production
✅Basic HTML validation to catch unclosed tags
📋One-click copy and file download
🎨Syntax-highlighted dark editor for comfortable editing
📱Works on all devices — desktop, tablet, mobile

Frequently Asked Questions

What is HTML formatting/beautifying?
HTML formatting adds proper indentation and line breaks to compressed or messy HTML code, making it human-readable. Beautified code is easier to debug, maintain, and collaborate on — it has zero effect on how the browser renders the page.
When should I minify vs beautify HTML?
Beautify during development to improve readability and debugging. Minify before deploying to production to reduce file size, improve page load speed, and boost Core Web Vitals scores — which directly affect SEO rankings.
Does reformatting HTML change how the page looks?
No. Whitespace between HTML tags is generally irrelevant to browsers. Formatting only affects code readability, not the visual output or functionality of the page.
What's the best indentation style for HTML?
Google's HTML/CSS style guide recommends 2-space indentation. Many teams use 4 spaces. Tab-based indentation is flexible since editors can display them at any width. Choose what your team agrees on and stay consistent.
`; updateStats(); } function updateStats() { const inp = document.getElementById('input').value; const out = document.getElementById('output').value; const tags = (inp.match(/<[^/][^>]*>/g) || []).length; document.getElementById('st1').textContent = 'Input: ' + inp.length.toLocaleString() + ' chars'; document.getElementById('st2').textContent = 'Output: ' + out.length.toLocaleString() + ' chars'; document.getElementById('st3').textContent = out.split('\n').length + ' lines'; document.getElementById('st4').textContent = tags + ' tags'; } function format() { const html = document.getElementById('input').value.trim(); if (!html) return; const indentType = document.getElementById('indentType').value; const size = parseInt(document.getElementById('indentSize').value) || 2; const indent = indentType === 'tabs' ? '\t' : ' '.repeat(size); const lowercase = document.getElementById('opt-lowercase').classList.contains('active'); const VOID = new Set(['area','base','br','col','embed','hr','img','input','link','meta','param','source','track','wbr']); const INLINE = new Set(['a','abbr','acronym','b','bdo','big','br','button','cite','code','dfn','em','i','img','input','kbd','label','map','object','output','q','samp','select','small','span','strong','sub','sup','textarea','time','tt','var']); const PRE = new Set(['pre','script','style','textarea']); let result = ''; let level = 0; let inPre = false; const regex = /||<([a-zA-Z][a-zA-Z0-9-]*)[^>]*\/?>|<\/([a-zA-Z][a-zA-Z0-9-]*)>|[^<]+/g; let m; while ((m = regex.exec(html)) !== null) { const token = m[0]; const openTag = m[1]; const closeTag = m[2]; if (token.startsWith('/g, '').replace(/\s+/g, ' ').replace(/>\s+<').replace(/\s+>/g, '>').replace(/<\s+/g, '<').trim(); document.getElementById('output').value = min; updateStats(); } function validate() { const html = document.getElementById('input').value; if (!html) return; const errors = []; const opens = (html.match(/<[a-z][^/][^>]*[^/]>/gi) || []).map(t => t.match(/<([a-z][a-z0-9-]*)/i)?.[1]?.toLowerCase()).filter(Boolean); const closes = (html.match(/<\/([a-z][a-z0-9-]*)>/gi) || []).map(t => t.match(/<\/([a-z][a-z0-9-]*)/i)?.[1]?.toLowerCase()).filter(Boolean); if (!html.includes(' tag'); if (!html.includes(' section'); if (!html.includes(' tag — required for SEO'); if (!html.includes('charset')) errors.push('⚠️ Missing charset meta tag'); if (opens.length !== closes.length) errors.push(`⚠️ Tag count mismatch: ${opens.length} opening vs ${closes.length} closing tags`); const eb = document.getElementById('errorBox'); if (errors.length === 0) { eb.style.background='#f0fff4'; eb.style.color='#22aa55'; eb.style.borderColor='#b0eecb'; eb.textContent='✅ No obvious errors found! HTML looks valid.'; } else { eb.style.background='#fff0f0'; eb.style.color='#cc3333'; eb.style.borderColor='#ffcccc'; eb.innerHTML = errors.join('
'); } eb.style.display = 'block'; } function copyOutput() { const out = document.getElementById('output').value; navigator.clipboard?.writeText(out).then(() => alert('Copied to clipboard!')); } function downloadOutput() { const a = document.createElement('a'); a.href = URL.createObjectURL(new Blob([document.getElementById('output').value], {type:'text/html'})); a.download = 'formatted.html'; a.click(); }