Free HTML & CSS Tools
Free browser-based tools for writing and fixing HTML. Format messy markup, check your code for errors, and build pages with a live preview. Every tool works without an account, and the code you paste stays on your device unless you choose to send it somewhere.
Available now
Online HTML Editor
A full code editor with live preview, a file manager and resizable panels. Write HTML, CSS and JavaScript and watch the page update as you type.
Open the editor → 🔧HTML Formatter
Turn minified or messy markup into clean, indented code in one step. Choose 2 spaces, 4 spaces or tabs, and format the CSS inside your style tags too.
Format HTML → ✅HTML Validator
Find unclosed tags, nesting mistakes, duplicate IDs and missing alt text as you type, with a plain-English fix for each one. Run a full W3C check when you’re ready to publish.
Check HTML →Coming soon
Meta Tag Generator
Title, description, Open Graph and Twitter card tags, ready to paste.
Coming soonHTML Minifier
Strip whitespace and comments to make pages smaller and faster.
Coming soonColor Picker
Pick colors and convert between HEX, RGB and HSL.
Coming soonCSS Gradient Generator
Build linear and radial gradients visually and copy the CSS.
Coming soonWhich tool do you need?
| If you want to… | Use this |
|---|---|
| Write a page and see it as you go | Online HTML Editor |
| Read code that’s squashed onto one line | HTML Formatter |
| Work out why a layout is broken | HTML Validator (instant check) |
| Confirm a page follows the HTML standard before it goes live | HTML Validator (W3C check) |
| Look up what a tag does and try it | HTML tag reference |
How the tools fit together
Each tool does one job, and they hand off to each other. Paste code from a CMS or a minified page into the formatter to make it readable, run it through the validator to find what’s wrong, then press Open in Editor to fix it with a live preview. You never have to copy and paste between tabs.