Format, validate and beautify JSON online. Minify, sort keys, auto-fix single quotes, comments and trailing commas, find errors by line and explore a collapsible tree.
Free, no sign-up
Runs in your browser
Your data stays private
How to use the JSON Formatter & Validator
Paste JSON or upload a .json file.
Choose Beautify or Minify, the indent size and options such as sort keys.
Copy the result, or open the Tree tab to explore it.
Why use this JSON Formatter & Validator
Exact error locationInvalid JSON shows the line, column and a pointer to the faulty character.
Auto-fix modeRepairs single quotes, trailing commas, comments, unquoted keys and True or None values.
Interactive treeCollapse and expand nodes, and click any key to copy its JSONPath.
Safety checksWarns about duplicate keys and numbers that lose precision.
Frequently asked questions
How do I format JSON?
Paste it and choose Beautify. The JSON is indented immediately and invalid JSON shows its error position.
Can it fix invalid JSON?
With "Auto-fix common mistakes" on, it repairs frequent problems such as trailing commas and single quotes, and lists what it fixed.
Is my JSON sent to a server?
No. Parsing and formatting happen entirely in your browser.