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	14,431	18,270
Forks	790	732
Open Issues	132	28
Last Commit	Mar 28, 2026	Mar 26, 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

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