Schema Drift

OpenAPI contract diff · free, no signup

Find breaking API changes
before your consumers do.

Paste two OpenAPI specs. Every change is graded by who it actually hurts, so adding a required request field is flagged while adding a response field is not. Runs entirely in your browser: nothing is uploaded.

Schema Drift is a free tool from Negi Ventures. Open source on GitHub.

Severity follows one rule: a request change hurts whoever calls you, a response change hurts whoever reads you. So removing a request field is tolerable and removing a response field is not, and a response enum gaining a value is riskier than it looks.

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