FREEDOM251

Freedom251 › Developer Tools

Free and open first

Best Apis in 2026

API tools help publish, protect, test, monitor, or manage interfaces between software services. This list covers gateways, management platforms, testing tools, and related services that run on the web, Linux, macOS, Windows, through an API, or in a self-hosted setup.

  1. 1

    Scalar

    Free plan Open source APILinuxMac+3

    Scalar brings several API documentation and management tools together, with hosted and self-hosted options.

    8.6 Free plan · paid from $150/mo Visit site
  2. 2

    Amazon API Gateway

    Free plan AndroidAPIiPhone+1

    Amazon API Gateway brings API creation, traffic controls, monitoring, and authorization into a managed cloud service.

    7.7 From $1 Visit site
  3. 3

    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.

    7.6 Free plan · paid from $9/user/mo (annual) · 14-day trial Visit site
  4. 4

    Checkly

    Free plan APILinuxWeb

    Checkly combines uptime monitors, browser-based checks, and scheduled Playwright suites with a code-oriented workflow.

    7.4 Free plan · paid from $24/mo Visit site
  5. 5

    Google Cloud Endpoints

    Free plan APILinuxMac+2

    Google Cloud Endpoints combines API lifecycle management, access policies, and analytics in a hybrid deployment. Consider the listed API-call ranges and prices when choosing a tier.

    7.4 Free plan · paid from $3 Visit site
  6. 6

    Assertible

    Free plan APIWeb

    Choose Assertible if you need HTTP service checks, deployment smoke tests, or API test synchronization with common specification formats and Postman collections.

    7.3 Free plan · paid from $25/mo 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.

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

    Kong Gateway

    Free plan APILinuxSelf-hosted+1

    Choose Kong Gateway if you need an API gateway with open-source availability and deployment options spanning on-premises, cloud, Kubernetes, and serverless environments.

    7.3 Pricing on request Visit site
  9. 9

    Apache APISIX

    Free plan APILinuxSelf-hosted

    APISIX combines API and AI gateway functions with broad protocol and plugin support. Its self-managed model and separate commercial support are important considerations for teams evaluating it.

    7.2 Free plan Visit site
  10. 10

    KrakenD API Gateway

    Free plan LinuxMacSelf-hosted+1

    KrakenD brings API composition, traffic controls, and multiple authentication options into a self-hosted gateway.

    7.2 Free plan Visit site
  11. 11

    Google Cloud API Gateway

    Free plan APIWeb

    Choose Google Cloud API Gateway when you need a managed API layer for supported backends, with authentication, traffic controls, and request monitoring.

    7.1 Free plan · paid from $3 Visit site
  12. 12

    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.

    7.1 Free plan · paid from $9/mo (annual) Visit site
  13. 13

    Oracle Cloud Infrastructure Container Registry

    Free plan APILinuxWeb
    7.0 Free plan Visit site
  14. 14

    Redocly

    by Redocly
    Free plan APIExtensionWeb

    Redocly brings API references, collaboration, governance, and monitoring into one product set, with an open-source CLI and VS Code extension.

    6.9 From $10/user/mo · 30-day trial Visit site
  15. 15

    Tyk API Management

    Free plan APILinuxSelf-hosted+1

    Tyk suits teams seeking API gateway controls alongside lifecycle management, analytics, and deployment choice.

    6.9 Pricing on request · 2-day trial Visit site
  16. 16

    Stoplight Elements

    Free plan Self-hostedWeb

    Stoplight Elements covers core interactive API documentation needs with OpenAPI support, code examples, and an embedded console.

    6.7 Free plan Visit site
  17. 17

    SwaggerHub

    by SwaggerHub
    Free plan Self-hostedWeb

    SwaggerHub brings API design, documentation, testing, and governance into a set of team tools.

    6.7 Pricing on request Visit site
  18. 18

    Gravitee API Management

    Free plan LinuxWebWindows
    6.6 Free plan · paid from $2,500/mo · 14-day trial Visit site
  19. 19

    API7 Enterprise

    Free trial APILinuxSelf-hosted+1

    API7 Enterprise combines lifecycle management, gateway policies, developer documentation, analytics, and multi-cluster organization.

    6.5 Pricing on request Visit site
  20. 20

    ReadyAPI

    Free trial APILinuxMac+3

    ReadyAPI covers several API testing needs, with distinct plans for testing, performance, and virtualization.

    6.0 14-day trial Visit site
  21. 21

    Google Apigee

    Paid Web

    Apigee offers several API management capabilities alongside pricing tiers based on proxy type, calls, and environments. Review the relevant usage and regional costs before choosing a plan.

    4.8 From $13 · 60-day trial Visit site
  22. 22

    Azure API Management

    Paid Web

    Azure API Management offers a broad API management feature set with tiers for serverless, evaluation, production, and enterprise use.

    4.7 Pricing on request Visit site
  23. 23

    IBM API Connect

    Paid Web
    4.7 From $83/mo (annual) · 30-day trial Visit site
  24. 24

    F5 NGINX App Protect DoS

    Paid Linux
    4.5 Pricing on request Visit site
  25. 25

    MuleSoft Omni Gateway

    Paid LinuxWeb

    MuleSoft Omni Gateway covers a wide protocol set with several authentication and traffic-management controls. The trial can help teams assess fit before requesting pricing.

    4.4 Pricing on request · 30-day trial 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

Review each tool's free-plan terms, entry-level paid price, trial period, deployment methods, protocol support, gateway functions, developer portal, analytics, and testing capabilities. If code access matters, check the open-source licence; a free plan or trial may have limits or an end date.

Questions

Can I use an API tool for free?

Yes. Free plans appear for Apache APISIX, Apidog, Assertible, Checkly, Google Cloud API Gateway, Google Cloud Endpoints, and Gravitee API Management. Check plan limits.

Which API tools have trials?

Apidog and Gravitee API Management show 14-day trial periods, while Google Apigee shows 60 days. Trial terms can differ from free-plan terms.

Are open-source API tools available?

Open-source code is available from items on this list. Read the licence to confirm whether its terms fit your plans for modification, self-hosting, or redistribution.

What platforms can these API tools run on?

Listed platforms include web, Linux, API, self-hosted setups, macOS, and Windows. Check the product's deployment options for your environment.

What should I compare between API tools?

Assess free-plan terms, starting paid price, gateway and developer-portal availability, analytics, deployment choices, supported protocols, and testing features.

More in Developer Tools