JSON Schema Validator
Check any JSON document against its schema with Ajv
Runs 100% in your browser — nothing is ever uploaded.
What is JSON Schema Validator?
Paste your JSON Schema and the document to check (separated by a ----- line) and get a precise validation report powered by Ajv — the industry-standard validator. Every violation is listed with its instance path and human-readable message, so you can fix API contracts and config files fast.
How to use JSON Schema Validator
- Paste your schema + JSON into the input box or click “Load sample” to try it.
- Adjust the options in the toolbar if needed (root name, format, delimiter …).
- Click the convert button — the report output appears instantly in the output pane.
- Copy the result with one click or download it as a file.
ConvertLab FAQ
Is the JSON Schema validator free?
Yes — 100% free, no signup, no limits, no watermarks. Use it as often as you like.
Which JSON Schema drafts are supported?
Validation is powered by Ajv with strict mode off, which supports draft-07 and the most common draft 2019-09/2020-12 keywords. All errors are collected in one pass with exact instance paths.
Is my data uploaded to a server?
No. Everything runs entirely in your browser with JavaScript — your data never leaves your device, which makes the tool safe even for confidential files.
Are these converters free?
Yes — every ConvertLab tool is 100% free with no signup, no limits and no ad walls.
Is my data uploaded anywhere?
No. All conversions (JSON, CSV, XML, YAML, INI, .env) run entirely in your browser. Nothing ever leaves your device.
Do these tools work offline?
Yes — once the page is loaded, every converter works without an internet connection.