JSON Schema to OpenAPI 3.1 Schema

Create an OpenAPI 3.1 document with the source schema placed under components.schemas for further API-specific editing.

JSON SchemaDraft 2020-12-style input

OpenAPI 3.1 starter—

—Properties

—Required paths

—$ref uses

—Max depth

This helper supports common schema structures and local analysis. Generated examples/code/docs are starter output, not a substitute for a complete schema implementation, language-specific code generator, or production validation suite.

Target-version conversion audit

Use the existing JSON Schema input, then preview a 3.1 or 3.0 handoff with explicit adjustment and loss warnings.

OpenAPI targetSchema name Wrap in a complete components/schemas starter

0Adjustments

0Warnings

0Local refs

0Output chars

Audited OpenAPI outputAdjustment report

How to use this JSON Schema to OpenAPI 3.1 Schema

Create an OpenAPI 3.1 document with the source schema placed under components.schemas for further API-specific editing.

Supported scope and limits

This browser-local helper is designed around common JSON Schema Draft 2020-12 structures, but it does not claim complete specification coverage. Remote references are not fetched, and generated examples, documentation, TypeScript, Zod, or OpenAPI output should be reviewed and refined against the real schema and application contract before production use.

Practical guide and verification

Use the product first, then apply these tool-specific checks to verify assumptions, interpret the result, and hand it off safely without moving the primary workflow below generic content.

Choose the OpenAPI target before converting

OpenAPI 3.1 aligns closely with JSON Schema 2020-12, while OpenAPI 3.0 uses a more limited Schema Object with different nullable and exclusive-bound conventions. A conversion that is nearly lossless for 3.1 can require rewrites or dropped keywords for 3.0. Record the target version with the output so later reviewers know which dialect rules were applied.

Treat every dropped keyword as a contract change

Conditional schemas, unevaluated constraints, content annotations, and newer array keywords may have no direct OpenAPI 3.0 equivalent. The audit panel lists adjustments and warnings instead of silently pretending full fidelity. Review each warning and decide whether the API contract needs a vendor extension, manual rewrite, or an OpenAPI 3.1 target.

Verify references after wrapping components

Moving definitions into components.schemas changes JSON Pointer paths. Check every local $ref after conversion and make sure the referenced schema exists in the generated document. Remote references are not fetched by this browser workflow, so external dependencies must be bundled or reviewed separately before the output is used for code generation or validation.

Validate the complete API document separately

A schema converter cannot infer paths, operations, parameters, security, responses, servers, or business rules from a JSON Schema alone. Even when the generated components are structurally sound, insert them into the real OpenAPI document and run a standards validator and your normal CI/code-generation tests before publishing the API contract.