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Best API Clients in 2026

API clients support work such as sending requests, inspecting results, and working with API documentation. Compare documentation support and automated test runs, then check GraphQL, gRPC, and WebSocket support against the protocols your work requires. Available platforms and team workspaces can help you assess whether a tool fits your setup, whether you work alone or with others. Free-plan availability and paid starting prices provide cost context. Postman, Apidog, and SoapUI are among the options shown. Consider which protocol support, testing features, and collaboration capabilities matter to your API workflow.

  1. 1

    SoapUI

    Free plan Open source APILinuxMac+2

    SoapUI Open Source offers API testing, mocking, and command-line automation across major listed protocols.

    9.3 Free plan Visit site
  2. 2

    Bruno

    Free plan Open source APIExtensionLinux+3

    Bruno pairs API testing and automation with Git-friendly plain-text collections and companion tools.

    9.2 Free plan · paid from $6/user/mo (annual) · 14-day trial Visit site
  3. 3

    HTTPie

    Free plan Open source LinuxMacWeb+1

    HTTPie offers command-line API testing alongside a graphical app for desktop and web. The CLI plan is open-source, while the Desktop and Web plan is in public beta; both are listed as free.

    9.2 Free plan Visit site
  4. 4

    xh

    Free plan Open source AndroidLinuxMac+1

    xh covers common HTTP request and response tasks from the command line, with authentication, TLS controls, and curl conversion.

    8.7 Free plan Visit site
  5. 5

    Postman

    by Postman
    Free plan ExtensionLinuxMac+2

    Postman combines API creation, testing, documentation, and monitoring in one platform, with a free plan and paid options. Check plan availability and the annual billing terms before choosing a tier.

    7.7 Free plan · paid from $9/mo (annual) Visit site
  6. 6

    Apidog

    Free plan APIExtensionLinux+4

    Apidog combines API design, testing, mocking, and documentation with specification-driven workflows and deployment choices. Check the plan details and database limits against your team's requirements.

    7.7 Free plan · paid from $9/user/mo (annual) · 14-day trial Visit site
  7. 7

    Insomnia

    Free plan LinuxMacSelf-hosted+1

    Insomnia covers API design and client workflows alongside mocking, CI/CD execution, and team collaboration.

    7.6 Free plan · paid from $12/user/mo · 14-day trial Visit site
  8. 8

    Hurl

    Free plan LinuxMacSelf-hosted+1

    Hurl combines request workflows, response assertions, and CI reporting in a free command-line tool. Check the listed Linux and Windows requirements before choosing an installation option.

    7.5 Free plan Visit site
  9. 9

    Hoppscotch

    Free plan APILinuxMac+3

    Hoppscotch covers API testing and collaboration, with a free tier and paid team and enterprise plans. Compare the listed plan details with the collaboration and access controls your team needs.

    7.5 Free plan · paid from $6/user/mo (annual) Visit site
  10. 10

    OpenReq

    Free plan ExtensionSelf-hostedWeb+1

    OpenReq offers broad API test workflows and documentation sharing without subscription tiers.

    7.5 Free plan Visit site
  11. 11

    Testfully

    by Testfully
    Free plan ExtensionLinuxMac+2

    Testfully combines API testing, monitoring, and team collaboration across cloud and offline workspaces.

    7.4 Free plan · paid from $14/user/mo (annual) · 14-day trial Visit site
  12. 12

    Altair GraphQL Client

    Free plan ExtensionLinuxMac+3

    Altair offers a broad set of GraphQL query and schema tools, with collaboration features through its Cloud offering.

    7.4 Free plan · paid from $7.99/user/mo Visit site
  13. 13

    Firecamp

    Free plan LinuxMacSelf-hosted+2

    Choose Firecamp if you need playgrounds for several API protocols, shared collections, and a free plan for a team of up to 5.

    7.4 Free plan Visit site
  14. 14

    Thunder Client

    by Thunder Client
    Free plan ExtensionLinuxMac+1

    Choose Thunder Client if you want an API client inside your IDE, with local data storage and graphical response validation.

    7.4 Free plan · paid from $3/user/mo (annual) · 14-day trial Visit site
  15. 15

    Kreya

    by Kreya
    Free plan LinuxMacWindows

    Kreya combines broad protocol support with scripted and snapshot testing, imports, and CI/CD use.

    7.3 Free plan · paid from $5/user/mo · 10-day trial Visit site
  16. 16

    grpcurl

    Free plan LinuxMacSelf-hosted+1

    Choose grpcurl when you need a free command-line way to invoke gRPC methods, inspect schemas, or work with streaming RPCs.

    7.3 Free plan Visit site
  17. 17

    Insomnium

    Free plan LinuxMacSelf-hosted+1

    Choose Insomnium if you want a free, local API client with broad protocol coverage and offline operation.

    7.3 Free plan Visit site
  18. 18

    API Dash

    Free plan iPhoneLinuxMac+1

    API Dash provides broad protocol coverage, request organization, response inspection, imports, and code generation at no stated cost.

    7.2 Open source Visit site
  19. 19

    Restfox

    Free plan ExtensionLinuxMac+3

    Restfox provides a broad set of request, scripting, plugin, and collection features without a paid plan. Its desktop-only local-file method is the main documented limitation.

    7.2 Open source Visit site
  20. 20

    httpYac

    Free plan ExtensionSelf-hosted

    Choose httpYac if you want a free way to create API requests in VS Code or run and test them from the CLI. Its notebook documentation and CI-focused CLI also suit those workflows.

    7.1 Free plan Visit site
  21. 21

    Vegha

    Free plan LinuxMacWindows

    Vegha combines a desktop API client with collection scripting, git tools, and a CLI that can output JUnit XML.

    7.1 Free plan Visit site
  22. 22

    Yaak

    Free plan LinuxMacWindows

    Yaak brings API requests and Git-oriented organization together in a desktop client with local data storage.

    7.1 Free plan · paid from $79/user/yr · 30-day trial Visit site
  23. 23

    Chapar

    Free plan LinuxMacWindows

    Choose Chapar if you want a free desktop client spanning REST, gRPC, and GraphQL, with scripts and CI-run test cases.

    7.1 Free plan Visit site
  24. 24

    grpcui

    Free plan LinuxMacSelf-hosted+2

    grpcui offers a browser-based way to build and inspect gRPC requests, including support for several schema sources and transport options.

    7.1 Open source Visit site
  25. 25

    Restish

    Free plan LinuxMacSelf-hosted+1

    Restish provides a broad command-line workflow for discovering, calling, filtering, and formatting REST APIs.

    7.1 Free plan Visit site

#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price

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