JSON formatter & validator
Pretty-print, validate and minify JSON, with error messages that point to the exact problem.
How it works
How to use the JSON Formatter tool
- 1
Paste or open JSON
Paste JSON into the input, or open a .json file from your device.
- 2
Choose formatting
Pick 2 spaces, 4 spaces, tabs or minified output, and optionally sort keys alphabetically.
- 3
Fix errors, then copy
Invalid JSON shows the line, column and a plain-English explanation. Copy or download the result.
Helpful error messages
Instead of a cryptic “Unexpected token”, FreeToolsDaily explains common mistakes: trailing commas, single quotes, unquoted keys, comments and missing brackets. “Show me” jumps the cursor straight to the problem in your input.
Safe for sensitive data
API responses and configuration files often contain tokens, emails or customer data. Because everything runs in your browser, nothing you paste is ever transmitted, which isn't true of many online formatters.
Limitations
We’d rather be upfront about what this tool can’t do yet:
- Very large documents (over about 20 MB) may be slow to format in the browser.
- JSON5 and JSON with comments aren't valid standard JSON and are reported as errors.
FAQ
Frequently asked questions
Is my text saved or sent anywhere?
What's the difference between formatting and minifying?
Does sorting keys change my data?
Why are comments flagged as errors?
Keep going