API Response Validator

// HOW TO USE

1. 01Paste the API response JSON into the response field (or click Load passing/failing sample).
2. 02Paste the expected JSON Schema to validate the response against.
3. 03Read the validation findings — each error shows the exact field path and reason.
4. 04Copy the findings (plain or as Markdown) into a bug report or CI ticket.

// WHEN TO USE

Use when you need to verify that an API response conforms to an expected JSON Schema contract, or to run fast structural checks on a pasted response without writing test code. Particularly useful for exploratory API testing, quick contract smoke-checks, and debugging why a response is failing schema validation in CI.

// WHAT BUGS THIS FINDS

• Missing required fields

  Backend drops a field that clients depend on — passes 200 status but breaks consumers downstream.

• Type mismatches

  A field declared as number in the schema is returned as a string — silent coercion in some clients hides the bug until a strict parser hits it.

• Null where disallowed

  Schema declares a field non-nullable but the API returns null under certain conditions — caught by schema validation, missed by status-code-only tests.

• Extra unexpected fields

  Additional fields leak internal data (user IDs, internal flags) that should not be in the public contract.

// QA USE CASES

// Related