JSON Validator
Check if a string is valid JSON. Reports the approximate line and column where a syntax error occurs. Runs entirely in your browser.
Processed in your browser · No upload
Loading tool…
Validation runs locally in your browser using native JSON.parse. Nothing is uploaded.
FAQ
- Does this send my JSON to a server?
- No. Validation happens entirely in your browser using the built-in JSON.parse.
- Can it pinpoint where the JSON is broken?
- Yes. The tool extracts the character position from the parser error and reports the matching line and column.
Related Tools
JSON Formatter
Pretty-print JSON with configurable indentation (2 spaces, 4 spaces, or tab). Runs entirely in your browser with friendly error messages for invalid input.
JSON Minifier
Compress JSON by removing all unnecessary whitespace. Shows the original and minified byte counts so you can see how much you saved.
JSON Diff
Compare two JSON documents and see added, removed, and changed keys. Uses the jsondiffpatch library and runs entirely in your browser.
UUID Generator
Generate RFC 4122 v4 UUIDs instantly in your browser. Choose how many to generate and copy the result with one click.
Base64 Encoder
Encode any UTF-8 text to Base64 online for free. Processed entirely in your browser — no data leaves your device.
Base64 Decoder
Decode Base64 strings back to readable UTF-8 text in your browser. Friendly error messages for invalid input.