Best API Design Tools in 2026
Updated
In short: Apidog is ranked #1 of 26 as of 4 October 2026, ahead of Pact and Postman. The best-ranked option with a free plan is Pact. The lowest first paid tier on this page is Apollo Studio at $5/mo.
API design tools can help teams describe interfaces, check contracts, and coordinate related work. Compared on, the entries cover OpenAPI and AsyncAPI support, contract validation, mock servers, Git synchronization, team collaboration, and included team seats. Free-plan availability and paid-from pricing provide further points of comparison. Apidog, Pact, and Postman are among the tools to assess, alongside oasdiff and WireMock. Consider which API specifications and validation checks are part of your workflow, then weigh the listed collaboration features and seat allowances against how you plan to work.
26 API design tools ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
API Design Tools, ranked on how quickly a newcomer can get going. 19 of the 25 on this page can be tried for free.
- 1 ApidogPaid from $9/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: yes
- 2 PactPaid from $115.42/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: yes
- 3 PostmanPaid from $9/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: yes
- 4 oasdiffPaid from $100/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: yes
- 5 WireMockFree plan
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: yes
- 6 GraphQL HivePaid from $20/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: not on record
- 7 OpenAPI StudioPaid from $9/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: not on record
- 8 SwaggerHubPaid from $61.67/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: not on record
- 9 PactFlowPaid from $115.42/mo
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: not on record
- 10 Swagger EditorFree plan
- Free to practise on: yes
- Free trial: yes
- Well documented: yes
- Runs where you work: not on record
- 11 Apollo StudioPaid from $5/mo
- Free to practise on: yes
- Free trial: not on record
- Well documented: yes
- Runs where you work: yes
- 12 MicrocksFree plan
- Free to practise on: yes
- Free trial: not on record
- Well documented: yes
- Runs where you work: yes
- 13 TypeSpecFree plan
- Free to practise on: yes
- Free trial: not on record
- Well documented: yes
- Runs where you work: yes
- 14 MockoonPaid from €10/mo
- Free to practise on: not on record
- Free trial: yes
- Well documented: yes
- Runs where you work: yes
- 15 MockServerFree plan
- Free to practise on: yes
- Free trial: not on record
- Well documented: yes
- Runs where you work: yes
- 16 RedoclyPaid from $10/mo
- Free to practise on: not on record
- Free trial: yes
- Well documented: yes
- Runs where you work: not on record
- 17 SchemathesisFree plan
- Free to practise on: yes
- Free trial: not on record
- Well documented: yes
- Runs where you work: yes
- 18 Stoplight ElementsFree plan
- Free to practise on: yes
- Free trial: not on record
- Well documented: yes
- Runs where you work: not on record
- 19 WSO2 API DesignerPaid from $119/mo
- Free to practise on: not on record
- Free trial: yes
- Well documented: yes
- Runs where you work: yes
- 20 MuleSoft ComposerPaid from $2,000/mo
- Free to practise on: not on record
- Free trial: not on record
- Well documented: yes
- Runs where you work: not on record
- 21 Smithy
- Free to practise on: not on record
- Free trial: not on record
- Well documented: not on record
- Runs where you work: yes
- 22 vacuum
- Free to practise on: not on record
- Free trial: not on record
- Well documented: not on record
- Runs where you work: not on record
- 23 MuleSoft Omni Gateway
- Free to practise on: not on record
- Free trial: not on record
- Well documented: not on record
- Runs where you work: not on record
- 24 Assertible
- Free to practise on: not on record
- Free trial: not on record
- Well documented: not on record
- Runs where you work: not on record
- 25 AsyncAPI Studio
- Free to practise on: not on record
- Free trial: not on record
- Well documented: not on record
- Runs where you work: not on record
Compare all 25 in a table
| # | Platform | Score | Free plan | From | Free plan | Paid from | OpenAPI support | AsyncAPI support |
|---|---|---|---|---|---|---|---|---|
| 1 | Apidog | 8.0 | Free plan | $9/mo | Yes | 9 /user/mo | — | — |
| 2 | Pact | 7.9 | Free plan | $115.42/mo | Yes | — | — | — |
| 3 | Postman | 7.9 | Free plan | $9/mo | Yes | — | — | — |
| 4 | oasdiff | 7.8 | Free plan | $100/mo | Yes | — | — | No |
| 5 | WireMock | 7.8 | Free plan | Free | Yes | — | Yes | — |
| 6 | GraphQL Hive | 7.6 | Free plan | $20/mo | Yes | — | — | — |
| 7 | OpenAPI Studio | 7.6 | Free plan | $9/mo | Yes | — | Yes | Yes |
| 8 | SwaggerHub | 7.6 | Free plan | $61.67/mo | — | — | — | — |
| 9 | PactFlow | 7.5 | Free plan | $115.42/mo | Yes | — | — | — |
| 10 | Swagger Editor | 7.5 | Free plan | Free | Yes | — | Yes | Yes |
| 11 | Apollo Studio | 7.4 | Free plan | $5/mo | Yes | — | — | — |
| 12 | Microcks | 7.4 | Free plan | Free | Yes | — | — | — |
| 13 | TypeSpec | 7.4 | Free plan | Free | — | — | Yes | No |
| 14 | Mockoon | 7.2 | No | €10/mo | Yes | — | — | — |
| 15 | MockServer | 7.2 | Free plan | Free | Yes | — | — | — |
| 16 | Redocly | 7.1 | No | $10/mo | No | 10 /user/mo | — | — |
| 17 | Schemathesis | 7.1 | Free plan | Free | Yes | — | — | — |
| 18 | Stoplight Elements | 6.9 | Free plan | Free | Yes | — | Yes | Yes |
| 19 | WSO2 API Designer | 6.9 | No | $119/mo | No | — | Yes | — |
| 20 | MuleSoft Composer | 5.9 | No | $2,000/mo | No | — | — | — |
| 21 | Smithy | 5.7 | No | — | — | — | Yes | — |
| 22 | vacuum | 5.6 | No | — | — | — | Yes | Yes |
| 23 | MuleSoft Omni Gateway | 5.4 | No | — | No | — | — | — |
| 24 | Assertible | 5.3 | No | — | Yes | — | — | — |
| 25 | AsyncAPI Studio | 5.3 | No | — | — | — | — | Yes |
Is your platform 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 The Geeks Club?
Apidog is ranked #1 of 26 with a score of 8.0. Pact is second and Postman 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, Apollo Studio has the lowest first paid tier we found: $5/mo.
How is this list ranked?
Ranked on how quickly a newcomer can get going: documentation depth, a free tier or trial, and the platforms it runs on. Paid placements never change a rank.