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Open-source projects tagged “API Client”.

Inspect repositories, licenses, activity, and alternatives across the API Client ecosystem.

5 projects connectedTag matches come from repository topics and catalog metadata.
Insomnia
Apache-2.0

The open-source, cross-platform API client for GraphQL, REST, WebSockets, SSE and gRPC. With Cloud, Local and Git storage.

InfrastructureOpen-source projects grouped in this category for discovery and comparison.2 projects#TypeScriptProjects tagged with this topic in the verified catalog.5 projectsGithub ActionsProjects tagged with this topic in the verified catalog.4 projectsJavaScriptProjects tagged with this topic in the verified catalog.4 projectsPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree39.9K2.4K27 hours ago
Alternatives toPostmanPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives+1
Scalar
MIT

Scalar is an open-source API platform:　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　🌐 Modern REST API Client　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　📖 Beautiful API References　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　✨ 1st-Class

InfrastructureOpen-source projects grouped in this category for discovery and comparison.2 projects#TypeScriptProjects tagged with this topic in the verified catalog.5 projectsGithub ActionsProjects tagged with this topic in the verified catalog.4 projectsJavaScriptProjects tagged with this topic in the verified catalog.4 projectsPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree15.6K89626 hours ago
Alternatives toPostmanPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives+2
Nango
License not declared

Build product integrations with AI.

AI & Machine LearningOpen-source projects grouped in this category for discovery and comparison.1 project#TypeScriptProjects tagged with this topic in the verified catalog.5 projectsGithub ActionsProjects tagged with this topic in the verified catalog.4 projectsJavaScriptProjects tagged with this topic in the verified catalog.4 projectsAI-nativeThis project includes AI-native capability signals in the catalog metadata.1 AI-native projectPipedreamProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…1 alternative
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree11.1K1.2K26 hours ago
Alternatives toPipedreamPipedreamProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…1 alternative+3
Firecamp
AGPL-3.0

Developer-first OpenSource API DevTool, Postman/Insomnia alternative.

Content & CollaborationOpen-source projects grouped in this category for discovery and comparison.2 projects#TypeScriptProjects tagged with this topic in the verified catalog.5 projectsGithub ActionsProjects tagged with this topic in the verified catalog.4 projectsJavaScriptProjects tagged with this topic in the verified catalog.4 projectsPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree2.6K1695 months ago
Alternatives toPostmanPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives+1
Echolon
MIT

A powerful, local-first API client with Git integration, offline support, and multi-protocol capabilities. Open source alternative to Postman.

Content & CollaborationOpen-source projects grouped in this category for discovery and comparison.2 projects#TypeScriptProjects tagged with this topic in the verified catalog.5 projectsapiProjects tagged with this topic in the verified catalog.5 projectsapi-clientProjects tagged with this topic in the verified catalog.5 projectsSelf-hostedThis project carries a self-hosting or local-deployment signal. Verify the official install guide before production use.1 self-hosted optionPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree534Mar 1, 2026
Alternatives toPostmanPostmanProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…3 alternatives+2
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