JSON Validator & Linter
Local-only guaranteeValidate JSON, see errors with line/column hints when available, and pretty-print clean output. Runs entirely in your browser.
Technical note: all parsing, validation, and transformations run in your browser (including the Web Worker); no network requests are made.
Tip: Paste API responses or config files to check validity.
Output
Validated JSON will appear here.
Workspace history
Privacy: local only (stored in your browser).No history yet. Validated inputs will appear here.
Tip: use the Share button to create a URL fragment for quick sharing without server uploads.
Developer tools
Schema, JSONPath, and key utilitiesJSON Schema validation
JSONPath / jq-style query
Run a query to see matching values.
Key tools & transforms
Transforms apply to the last validated JSON and replace the input.
How to use
- Paste JSON and click Validate (or leave auto-validate on).
- Toggle trim/JSON5 if your input includes trailing commas/comments.
- Copy or download the formatted output; review before/after size.
FAQ & privacy
Local only? Yes. Everything runs in your browser; no data is uploaded.
JSON5? Enable the toggle for JSON5 features (comments, trailing commas). Output is normalized to strict JSON.
Schema validation? Use the Developer tools panel to paste a schema and validate your JSON.