Why it exists
API specs often describe internal systems that shouldn't be uploaded to a third-party service. Swagger's online converter sends your spec to its server. SpecLift runs the same conversion entirely in your browser, and fixes the places where Swagger's output is invalid or loses data.
| SpecLift | converter.swagger.io | |
|---|---|---|
| Spec stays on your machine | ✅ | ❌ |
| Same conversion rules as Swagger | ✅ | ✅ |
| Valid OpenAPI 3 when Swagger's isn't | ✅ | ❌ |
| Works offline, no account, no tracking | ✅ | ❌ |
Highlights
- Two modes. Fix Swagger bugs (the default) keeps Swagger's rules and fixes its known bugs. Swagger-exact reproduces converter.swagger.io byte for byte, key order included.
- JSON and YAML, in and out. Paste, open or drop files up to 10 MB. YAML is read with the same YAML 1.1 rules Swagger uses.
- A real editor. Syntax highlighting, line numbers, error markers and live conversion as you type.
- Private by design. No backend, uploads, accounts, analytics, telemetry or third-party scripts.
Under the hood
The converter is a TypeScript port of Swagger's own converter (swagger-parser and swagger-core) written as a pure function with no network access. Swagger-exact mode is tested against converter.swagger.io: 99 real-world APIs from APIs.guru, from 1 KB to 1 MB, came out identical.
Get involved
Report a bug or request a feature. The project is MIT licensed.