AnyTool
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How do I validate JSON against a JSON Schema?

Paste your schema and JSON document into AnyTool's JSON Schema Validator and it reports PASS/FAIL with path-precise errors. It supports Draft-07, 2019-09, and 2020-12 and runs entirely in your browser, so your data is never uploaded.

  • Draft-07, 2019-09, and 2020-12 support via AJV
  • Path-precise errors with line/column highlighting
  • Live validate-as-you-type; format JSON and schema
  • 100% in your browser — no upload, no signup, free

What is

JSON Schema Validation

JSON Schema validation checks whether a JSON document conforms to a schema that defines its required fields, types, formats, and constraints. The validator reports each violation with the path to the offending value.

Developer Tools

Related terms

JSON SchemaAJVDraft 2020-12Data Validation

How to Validate JSON Against a Schema

Validate a JSON document against a JSON Schema entirely in your browser.

20 secWeb browser
  1. 1

    Paste the schema

    Add your JSON Schema and select (or auto-detect) the draft.

  2. 2

    Paste the JSON

    Add the JSON document to validate.

  3. 3

    Read the results

    See PASS/FAIL with path-precise errors; click an error to jump to it.

Result: A validation report with error locations

Frequently Asked Questions

No — validation runs entirely in your browser, so your data and schema are never uploaded.

AnyTool validates with AJV bundled in-page (no runtime CDN), so your JSON and schema never reach a server — directly beating the two most popular validators (jsonschemavalidator.net and Liquid), which are server-side.

Draft-07, Draft 2019-09, and Draft 2020-12.

The validator ships AJV with per-draft entry points and ajv-formats, so it covers Draft-07, 2019-09, and 2020-12 client-side — going beyond the Draft-07-only tools, and it can auto-detect the draft from the schema's $schema.

Yes — it maps each error to a line and column and highlights it in the editor.

AJV returns the instance path for every error; the tool resolves that to an exact line/column, lists all errors, and lets you click one to jump to the offending value.

Detailed Explanation

Methodology

How JSON Schema Validation Works

AnyTool validates JSON against a schema with AJV, the fastest JavaScript JSON Schema validator, supporting Draft-07, Draft 2019-09, and Draft 2020-12 via per-draft entry points plus ajv-formats for format keywords. The draft can be auto-detected from the schema's $schema. AJV returns an instancePath for each error, which the tool resolves to an exact line and column so failing nodes are highlighted in the editor and clickable. Validation is live (compile once per schema change, re-run on each data edit) and runs client-side, so JSON and schema are never uploaded.

  • AJV with Draft-07, 2019-09, and 2020-12 support
  • ajv-formats for email/date-time/uri keywords
  • instancePath mapped to exact line/column
  • $ref / $defs resolution; meta-schema sanity check
  • Bundled, no runtime CDN; no upload
Privacy & Security

Privacy vs Server-Side Validators

The two most-trafficked validators (jsonschemavalidator.net and Liquid) process JSON and schema on their servers and impose size caps. AnyTool validates entirely in the browser with no upload and no size limit, so sensitive payloads and proprietary schemas stay on the device. Remote http(s) $refs are not auto-fetched by design — paste additional schemas to register them locally.