About JSON / HTML Formatter
Format, minify and validate JSON and HTML without leaving your browser. Paste in messy data, get back perfectly indented output — or strip every byte of whitespace for production. Errors are highlighted with the exact line and column.
Why use JSON / HTML Formatter?
- JSON pretty print and minify
- HTML pretty print and minify
- Live syntax validation with error position
- Runs entirely in the browser
How it works
- 1Paste your JSON or HTML.
- 2Click Format or Minify.
- 3Copy the cleaned-up output.
Frequently asked questions
Is my data sent to a server?
No. All formatting and validation runs locally in your browser.
Why is my JSON invalid?
Common causes: trailing commas, single quotes, unquoted keys, or comments — none of which are allowed in strict JSON.