How to json schema validator without breaking your data

An upstream service changes a field from a string to a number. Nothing crashes; the value is silently coerced; two weeks later a report is wrong and nobody knows which release did it.

You see this most often in API contracts, webhook consumers, test fixtures. Reading a payload by eye does not scale past a handful of fields, and type errors are invisible until arithmetic happens.

Doing it in four steps

1. Paste the schema
2. Paste a payload
3. Read the violation paths
4. Fix the producer or the schema

The whole thing runs locally in the browser tab: no upload, no account, no queue. When the page says "removed 37 lines", that number comes from the file you just pasted, not from a sample.

Every violation reports its full path, so a nested array element is identified precisely instead of being described as "somewhere in the payload".

For the full picture — imports, feeds, variants, identifiers — see the pillar guide: Shopify product data management.

Try it on your own file

Open JSON Schema Validator and paste a sample. It is free, it does not store anything, and you do not need an account. If the file is sensitive, save the page locally and run it offline.

Questions people ask

Which schema features are supported?

Type, required, properties, items and enum — the subset that catches real breakage.

Does it report every violation?

Yes, it walks the whole document and lists each path, not just the first.