JSON Schema Validator API

POST

Catch invalid JSON payloads before they hit your database.

JSON Schema Validator tests any JSON object against a provided JSON Schema definition to verify data structures and types. It reports pass-fail status and total error count, while paid plans add specific error messages.

Try it — live request, no key required

Request
POSTapi.apiverve.com/v1/jsonschemavalidator
Body
Verification
Format

No key required to try it. Get a key to use it in your app.

Example
{
  "status": "ok",
  "error": null,
  "data": {
    "valid": true,
    "errors": [],
    "error_count": 0
  }
}

About the JSON Schema Validator API

JSON Schema Validator works by comparing JSON data against a JSON Schema definition. It validates types, required fields, string patterns, numeric ranges, array constraints, and format specifications.

What people use it for

API Validation
Validate incoming API request payloads against defined schemas before processing to ensure data quality
Configuration Files
Verify configuration files match expected schemas before deployment to prevent runtime errors
Data Quality
Validate data integrity in ETL pipelines by checking against schemas during data transformation
Contract Testing
Ensure API responses match contract specifications by validating against JSON schemas in tests

Ways to call it

One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.

JSON
Default REST response
XML
Markup format
YAML
Human-readable
CSV
Tabular export
Beta
GraphQL
Query language
New
MCP
For AI agents

Other ways to use JSON Schema Validator

Same data, same APIVerve account, same credit balance — one key works on all of them.

Questions.

Common questions about the JSON Schema Validator API.

Read the docs →
Is it cheap enough to validate every incoming API request?
Yes. Each validation costs 2 credits, which works out to about $0.0003 per call on the Starter plan, or $0.30 per 1,000 requests. The Starter plan provides enough credits for 100,000 validations per month, while the Free plan includes 100 calls each month to test your schemas.
Do I get the detailed validation error messages on the Free plan?
No. The Free plan provides the validation status and the error count, but the list of error messages is a premium field. Upgrading to any paid plan unlocks the errors array so you can see field-level explanations of what failed.
What schema rules and constraints does the validator support?
The validator checks data types, required fields, string patterns, numeric ranges, array constraints, and format specifications. You provide both the JSON Schema definition and the JSON data to validate in the request body.
Can I validate configuration files as well as API payloads?
Yes. As long as your data and schema are valid JSON objects, you can validate configuration files, incoming webhook payloads, or test fixtures for contract testing. The validator evaluates the data object directly against your supplied schema object.
What does the response return when a payload fails validation?
When validation fails, the valid field is set to false and error count indicates the number of failed constraints found. On paid plans, the errors field lists the specific violation messages, whereas on the Free plan that field is omitted.

Ready to build with JSON Schema Validator? Start with 200 free credits — one key unlocks all 300+ APIs.

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