Scalar vs Yaak

Comparing two open source alternatives to Postman. Use the comparison below to decide which one fits your needs.

Scalar

MIT

Scalar is an open-source API platform:　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　🌐 Modern Rest API Client　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　📖 Beautiful API References　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　✨ 1st-Class OpenAPI/Swagger Support

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Yaak

MIT

Local-first desktop API client for REST, GraphQL, gRPC, WebSocket, and SSE — Git-friendly collections, a CLI, and no cloud lock-in.

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Side-by-side comparison

	Scalar	Yaak
License	MIT	MIT
Self-hostable	No	No
GitHub Stars	16,384	19,456
Forks	970	848
Open Issues	61	18
Last Commit	Nov 8, 2026	Nov 8, 2026
First Released	Aug 16, 2023	Feb 16, 2023
Categories	API Development & Testing Tools	API Development & Testing Tools
Tags	#API #api client #rest #http client	#API #rest #http client #api client #GraphQL

GitHub stars over time

Scalar16,384

Yaak

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