Best API Mocking Tools in 2026
Updated
In short: Knockout API is ranked #1 of 27 as of 3 October 2026, ahead of Microcks and Mockfly. The best-ranked option with a free plan is Microcks. The lowest first paid tier on this page is Knockout API at $0.02/mo.
When building against an API that is not ready—or when you need controlled behavior for development—mocking tools can provide simulated responses. Compare supported protocols and request matching alongside dynamic responses to see how each entry describes its mock behavior. OpenAPI import and mock data generation may also matter, as can local deployment, free plans, and paid-from pricing. WireMock and MockServer lead the displayed entries, with Microcks next; WireMock appears again before Mockzilla, Mockfly, and moqapi.dev. Use the listed capabilities to weigh configuration and deployment needs against the API workflow you already run.
27 API mocking tools ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
| # | Platform | Score | Why | From | Free plan | Paid from | Dynamic responses | |
|---|---|---|---|---|---|---|---|---|
| 1 |  Knockout API | 7.4 | RecognisedAPIDocumented | $0.02/mo | Yes | — | — | View |
| 2 | Microcks | 7.4 | RecognisedAPIDocumented | Free | Yes | — | — | View |
| 3 |  Mockfly | 7.4 | RecognisedAPIDocumented | €15/mo | Yes | — | Yes | View |
| 4 |  Mockzilla | 7.4 | RecognisedAPIDocumented | $10/mo | Yes | 10 /mo | Yes | View |
| 5 |  MockAPI | 7.3 | RecognisedAPIDocumented | $2.92/mo | Yes | — | Yes | View |
| 6 |  moqapi.dev | 7.3 | RecognisedAPIDocumented | $29/mo | Yes | 29 /mo | Yes | View |
| 7 | MockServer | 7.2 | RecognisedAPIDocumented | Free | Yes | — | — | View |
| 8 | WireMock | 7.2 | RecognisedAPIDocumented | Free | Yes | — | — | View |
| 9 | WireMock | 7.2 | RecognisedAPIDocumented | Free | Yes | — | — | View |
| 10 | Parasoft SOAtest | 6.9 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 11 | Hoverfly | 6.7 | RecognisedAPIDocumented | $10/mo | No | 10 /mo | — | View |
| 12 | Mock Service Worker | 6.0 | RecognisedAPIDocumented | — | Yes | — | Yes | View |
| 13 |  OpenAPI Mock | 6.0 | RecognisedAPIDocumented | — | — | — | Yes | View |
| 14 |  Imposter | 5.8 | RecognisedAPIDocumented | — | — | — | Yes | View |
| 15 | Stoplight Elements | 5.8 | RecognisedAPIDocumented | Free | Yes | — | — | View |
| 16 | Beeceptor | 5.4 | RecognisedAPIDocumented | — | Yes | 10 /mo | — | View |
| 17 | Mockoon | 5.4 | RecognisedAPIDocumented | — | Yes | 100 /mo | — | View |
| 18 | Stoplight Prism | 5.2 | RecognisedAPIDocumented | — | Yes | — | — | View |
| 19 |  OpenAPI Server | 5.1 | RecognisedAPIDocumented | — | — | — | Yes | View |
| 20 |  API-Mocked | 5.0 | RecognisedAPIDocumented | — | — | — | Yes | View |
| 21 |  json-server | 5.0 | RecognisedAPIDocumented | — | — | — | Yes | View |
| 22 |  Mirage JS | 5.0 | RecognisedAPIDocumented | — | — | — | Yes | View |
| 23 |  Mocki | 5.0 | RecognisedAPIDocumented | — | No | 15 /mo | Yes | View |
| 24 |  MockPilot | 5.0 | RecognisedAPIDocumented | — | — | — | — | View |
| 25 |  Mockttp | 5.0 | RecognisedAPIDocumented | — | — | — | Yes | View |
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 mocking tool is ranked first on Inferse?
Knockout API is ranked #1 of 27 with a score of 7.4. Microcks is second and Mockfly third.
How many of these have a free plan?
10 of the 25 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, Knockout API has the lowest first paid tier we found: $0.02/mo.
How is this list ranked?
Ranked on what each maker publishes, open and connectable first: a public API, open-source code, the depth of its documentation and a free tier to try it on. Model lists are sorted by the figure in their title, exactly as each provider publishes it. Paid placements never change a rank.