Best API Design Tools in 2026
Updated
In short: Apidog is ranked #1 of 26 as of 4 October 2026, ahead of Apollo Studio and Microcks. The best-ranked option with a free plan is Apollo Studio. The lowest first paid tier on this page is Apidog at $2.25/mo.
API design tools support the work of describing and shaping interfaces, with different options for specifications, validation, and team workflows. Compare OpenAPI and AsyncAPI support, contract validation, mock servers, and Git synchronization. Team collaboration and included team seats can help you assess how tools fit shared work, while free-plan availability and paid-from pricing provide plan details to consider. The ranking begins with Apidog, Postman, and OpenAPI Studio, followed by options including SwaggerHub and TypeSpec. Think about the specifications and validation steps your work calls for, and compare the collaboration features and mock-server support alongside them.
26 API design tools ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
Recognised 40% · Phone app 26% · Documented 20% · Free plan 14% of the score
- 1 Apidog No phone app RecognisedPhone appDocumentedFree plan 6.4$2.25/mo Mock server: Yes
- 2 Apollo Studio No phone app RecognisedPhone appDocumentedFree plan 6.4$5/mo
- 3 Microcks No phone app RecognisedPhone appDocumentedFree plan 6.4Free
- 4 OpenAPI Studio No phone app RecognisedPhone appDocumentedFree plan 6.4$9/mo OpenAPI support: YesAsyncAPI support: Yes
- 5 Pact No phone app RecognisedPhone appDocumentedFree plan 6.4$115.42/mo Mock server: Yes
- 6 Postman No phone app RecognisedPhone appDocumentedFree plan 6.4$9/mo Mock server: Yes
- 7 TypeSpec No phone app RecognisedPhone appDocumentedFree plan 6.4Free OpenAPI support: YesAsyncAPI support: NoMock server: Yes
- 8 GraphQL Hive No phone app RecognisedPhone appDocumentedFree plan 6.3$20/mo Mock server: Yes
- 9 oasdiff No phone app RecognisedPhone appDocumentedFree plan 6.3$100/mo AsyncAPI support: No
- 10 PactFlow No phone app RecognisedPhone appDocumentedFree plan 6.3$115.42/mo Mock server: Yes
- 11 Stoplight Elements No phone app RecognisedPhone appDocumentedFree plan 6.3Free OpenAPI support: YesAsyncAPI support: YesMock server: No
- 12 Swagger Editor No phone app RecognisedPhone appDocumentedFree plan 6.3Free OpenAPI support: YesAsyncAPI support: Yes
- 13 SwaggerHub No phone app RecognisedPhone appDocumentedFree plan 6.3$61.67/mo
- 14 WireMock No phone app RecognisedPhone appDocumentedFree plan 6.3Free OpenAPI support: YesMock server: Yes
- 15 MockServer No phone app RecognisedPhone appDocumentedFree plan 6.2Free
- 16 Schemathesis No phone app RecognisedPhone appDocumentedFree plan 6.2Free
- 17 Redocly No phone app RecognisedPhone appDocumentedFree plan 5.8$10/mo
- 18 WSO2 API Designer No phone app RecognisedPhone appDocumentedFree plan 5.5$119/mo OpenAPI support: Yes
- 19 MuleSoft Composer No phone app RecognisedPhone appDocumentedFree plan 5.3$2,000/mo
- 20 Mockoon No phone app RecognisedPhone appDocumentedFree plan 5.1€10/mo
- 21 Smithy No phone app RecognisedPhone appDocumentedFree plan 5.1 OpenAPI support: Yes
- 22 vacuum No phone app RecognisedPhone appDocumentedFree plan 5.1 OpenAPI support: YesAsyncAPI support: Yes
- 23 Assertible No phone app RecognisedPhone appDocumentedFree plan 4.9
- 24 AsyncAPI Studio No phone app RecognisedPhone appDocumentedFree plan 4.9 AsyncAPI support: Yes
- 25 MuleSoft Omni Gateway No phone app RecognisedPhone appDocumentedFree plan 4.9
Is your app on this list?
Numbered spots on this list can be sponsored. They are labelled, and the editorial order and scores never change for payment.
Questions about this list
Which API design tool is ranked first on Samsung Mobile US Press?
Apidog is ranked #1 of 26 with a score of 6.4. Apollo Studio is second and Microcks third.
How many of these have a free plan?
16 of the 25 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, Apidog has the lowest first paid tier we found: $2.25/mo.
How is this list ranked?
Ranked mobile-first: a phone app alongside the web or desktop product, a free tier and the depth of its documentation. Paid placements never change a rank.