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

The most intuitive desktop API client. Organize and execute REST, GraphQL, WebSockets, Server Sent Events, and gRPC 🦬

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Side-by-side comparison

	Scalar	Yaak
License	MIT	MIT
Self-hostable	No	No
GitHub Stars	16,097	19,212
Forks	937	811
Open Issues	76	17
Last Commit	Sep 12, 2026	Sep 14, 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

GitHub stars over time

Scalar16,097

Yaak

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