Batch JSON Validator

Drop as many .json files as you like and validate all of them at once, right in your browser - optionally against a JSON Schema. See which files pass, which fail, and exactly why - nothing is uploaded anywhere.

What this tool does

This checks JSON syntax across many files at once instead of one at a time - useful for validating a folder of config files, API fixtures, or exported data before a deploy or migration. Paste a JSON Schema into the optional box above the drop zone to also validate every file's structure - required fields, types, and constraints - not just its syntax. Each file is checked independently; a problem in one file doesn't stop the rest from being checked.

Step-by-step

  1. Optionally paste a JSON Schema into the "Validate against a JSON Schema" box.
  2. Drag a folder's worth of .json files onto the drop zone, or click it to browse.
  3. Every file is validated immediately - see a pass/fail count at the top.
  4. Click any failed file to expand its exact error - a syntax error with line and column, or a schema violation with the failing path and rule.

Privacy

All parsing and schema validation happens locally in your browser, using the same Ajv-based engine as our JSON Schema Validator. Files are never uploaded, and nothing is retained after you leave the page.

Just checking a single file? Try our JSON Schema Validator or single-file Validator.

FAQ

What does the Batch JSON Validator check?

By default it checks that each file you drop is syntactically valid JSON - the same check as our JSON Validator, run across every file at once. If you paste a JSON Schema into the optional schema box, every file is also validated against that schema, so you can catch structural problems (missing fields, wrong types, failed constraints) across a whole batch, not just syntax errors.

How many files can I validate at once?

There's no hard limit - drop as many .json files as you like. Very large batches (hundreds of files, or individually huge files) will take longer since everything runs in your browser's memory.

Does this validate against a JSON Schema too?

Yes - paste or type a JSON Schema into the optional schema box above the drop zone. Every file you drop (or already-dropped files, if you add a schema afterward) is then checked against it using the same Ajv-based engine as our JSON Schema Validator, in addition to the syntax check.

What happens if my schema itself is invalid?

You'll see a clear error where you can edit the schema, and files won't be checked against it until it's fixed - so you never get misleading "valid" results from a broken schema.

Are my files uploaded to a server?

No. Every file is read and parsed locally in your browser. Nothing is uploaded, logged, or stored.

Can I see the exact error in an invalid file?

Yes - click a failed file's row to expand its error message, including the line and column where the parser stopped, when available.

Can I validate YAML or XML files in batch?

Not yet - the batch validator currently supports JSON only. Use our single-file Validator for YAML and XML.

Is my data uploaded to a server?

No. All tools run locally in your browser; your data isn't sent to any server.

Can I use the tool offline?

After the page loads once, most browsers will allow basic offline usage because processing is entirely client-side.

Can I beautify JSON?

Yes - use the Beautify actions in each tool where applicable.

Do you keep my files?

No. All tools run locally in your browser; data is not uploaded to any server.

Is there a size limit?

Large inputs are limited by your browser memory; for most cases typical files work fine.

Is it free?

Yes, All tools are 100% free and no sign-up required.