All tools

OpenAPI & Swagger Validator Viewer

Validate OpenAPI 3.x JSON or YAML, resolve local references, and browse operations and components.

OpenAPI document
Validation findings

Run the validator to check structure, path parameters, responses, and local $ref targets.

Endpoints

No operations to show yet.

The document is parsed locally. This is a focused structural debugger, not a replacement for a complete OpenAPI conformance implementation or remote-reference resolver.

API documents are parsed locally in your browser. Remote $ref URLs are deliberately not fetched, preventing unexpected disclosure or network access.

Overview

Validate OpenAPI 3.0 and 3.1 JSON or YAML, resolve local references, catch common operation mistakes, and browse endpoints.

Start with one of the included examples, inspect every finding, and verify consequential changes against the linked primary documentation and your own environment.

Use cases

When to use it

  • Example 1.Check path parameters, required responses, version and info fields, and unresolved local $ref pointers.
  • Example 2.Render a navigable method, path, summary, and operationId list for contract review.

When it's not enough

  • Production guarantees.A point-in-time tool result cannot prove every runtime, resolver, client, or edge location behaves the same way.
  • Blind automation.Review generated output and findings before committing configuration or security changes.

How to use it

  1. 1

    Load or paste a representative input

    Check path parameters, required responses, version and info fields, and unresolved local $ref pointers.

  2. 2

    Run the focused checks

    Read the exact path, record, operation, or certificate field attached to each finding.

  3. 3

    Verify and apply

    Use OpenAPI 3.1 validation mistakes and the related tools to confirm the fix before release.

Common errors and fixes

The input is incomplete or malformed

Reduce it to the smallest reproducible sample, correct the parse error, and rerun the check.

The tool passes but production still fails

Compare environment-specific inputs, network vantage points, versions, caches, and full standards conformance.

Frequently asked questions