How do I validate JSON against a schema online?

Paste the JSON Schema into the schema editor, paste your JSON data into the data editor, and click Validate JSON Schema. The tool checks required fields, data types, enums, patterns, and other schema rules entirely in your browser.

Is this the right tool for JSON validation schema checks?

Yes. Use this page when you need to validate JSON against a schema definition rather than only checking whether the JSON syntax is valid.

Can I validate a JSON object against a schema online?

Yes. Paste the JSON object or payload into the data editor, paste the schema into the schema editor, and run validation to see whether the object matches required fields, data types, enums, and other schema rules.

How is JSON schema validation different from JSON validation?

JSON validation checks syntax only. JSON schema validation checks whether valid JSON also follows structural rules such as required fields, data types, enums, and minimum values.

Can I use this as a schema JSON validator for API payloads?

Yes. Paste the schema that defines the payload contract and the request or response body you want to test. Validation happens entirely in your browser, which makes it useful for contract checks before deployment.

What does this JSON schema validator check?

JSON Schema rules like required, minimum, maximum, enum, pattern, array items, and additionalProperties are supported through Ajv so you can check both structure and value constraints.

Is my schema or data uploaded anywhere?

No. Schema compilation and validation run locally in your browser.

Developer Tools

JSON Schema Validator Online

Use this JSON schema validator online to validate JSON against a schema, run JSON schema validation on a JSON object or API payload, check JSON schema errors, and confirm request bodies, response payloads, config files, and webhook samples match the expected structure. This is the right tool when basic JSON validation passes but the data still needs schema-level checks.

JSON Schema

10 lines • 246 chars

Paste the schema that defines your JSON contract, required fields, allowed values, and API validation rules.

Quick examples

JSON Data

5 lines • 66 chars

Paste the request body, response body, or config JSON you want to validate against the schema.

Quick examples

Usage notes

Use this when you need to validate JSON with a schema, not just confirm the payload parses.
If the schema or payload came from logs, docs, or chat, clear syntax problems in /developer-tools/json-validator before schema validation.
Open either editor in fullscreen mode when you need to inspect long API payloads or large schemas.
Set additionalProperties to false when you want schemas to reject unexpected fields.
Schema validation is ideal for API payloads, config files, webhook samples, and contract checks before deployment.

Guide: Validate JSON Against a Schema Guide: Validate API Payloads with JSON Schema Guide: JSON Schema Examples for API Payloads JSON Validator JSON Formatter Compare: JSON Validator vs Schema Validator All Developer Tools

How to Use This Tool

1Paste or edit a JSON Schema in the first text area.
2Paste the JSON data you want to test in the second text area.
3Click Validate JSON Schema to compare the data with required fields, types, enums, patterns, and other schema rules.
4Review the result and fix any required fields, types, unexpected properties, or validation mismatches.

Frequently Asked Questions

How do I validate JSON against a schema online?: Paste the JSON Schema into the schema editor, paste your JSON data into the data editor, and click Validate JSON Schema. The tool checks required fields, data types, enums, patterns, and other schema rules entirely in your browser.
Is this the right tool for JSON validation schema checks?: Yes. Use this page when you need to validate JSON against a schema definition rather than only checking whether the JSON syntax is valid.
Can I validate a JSON object against a schema online?: Yes. Paste the JSON object or payload into the data editor, paste the schema into the schema editor, and run validation to see whether the object matches required fields, data types, enums, and other schema rules.
How is JSON schema validation different from JSON validation?: JSON validation checks syntax only. JSON schema validation checks whether valid JSON also follows structural rules such as required fields, data types, enums, and minimum values.
Can I use this as a schema JSON validator for API payloads?: Yes. Paste the schema that defines the payload contract and the request or response body you want to test. Validation happens entirely in your browser, which makes it useful for contract checks before deployment.
What does this JSON schema validator check?: JSON Schema rules like required, minimum, maximum, enum, pattern, array items, and additionalProperties are supported through Ajv so you can check both structure and value constraints.
Is my schema or data uploaded anywhere?: No. Schema compilation and validation run locally in your browser.

Quick Reference

What this JSON schema validator does

Validate JSON schema online

Paste your JSON instance and schema, get instant validation results — entirely in your browser.

Check JSON schema rules

Verify required fields, types, enums, patterns, nesting, array shape, and additionalProperties.

Verify JSON schema for API payloads

Confirm request and response bodies match the contract before QA and release.

Validate JSON object structure

Catch wrong types, missing required keys, and unexpected fields that syntax-only validators ignore.

Best Next Step

Use schema validation when syntax is not the real problem

JSON Schema validation matters most after the payload already parses. If the JSON is readable but the endpoint still rejects it, this is usually a contract problem rather than a formatting problem. That is where /developer-tools/json-schema-validator wins over a basic syntax check.

Fastest debugging flow

Start with /developer-tools/json-validator if you suspect malformed JSON. Once syntax is clean, validate the JSON object against the schema here. If the mismatch is still not obvious, compare a failing sample with a known-good one in /developer-tools/text-diff.

Best supporting pages

Use /guides/how-to-validate-json-against-schema for the general browser workflow, /guides/how-to-validate-api-payloads-with-json-schema when the issue sits inside requests or responses, and /compare/json-validator-vs-json-schema-validator when the team keeps mixing up syntax and schema checks.

Best use cases

Validate API request bodies before QA or release.
Check config files against required fields and allowed values.
Confirm webhook samples still match the expected contract after provider changes.