Mock Service Worker vs Mockoon
Feature checklists rarely decide anything. What decides it is the pricing metric, who has to write the tests, and which limitation you can live with.
Entry price
Free and open source
Open sourceFrom $100 per month (Team, billed annually, up to 5 members)
Free tierWhat drives the bill
The metric that actually scales your invoice.
Free and open source. You pay in engineering time and CI minutes.
Free locally and forever; the paid cloud tier adds hosted mocks and team sync. Team covers 5 members, 3 cloud-deployed mocks and 100k calls a month, with Enterprise on a quote. Work emails get a 14-day trial, others 7 days with a card.
Free tier
Everything, self-hosted
The desktop app and CLI are free and open source.
Open source
MIT
MIT
Self-hostable
No-code authoring
Languages
Platforms
Fits teams
Adoption
Category standard
OSS community · since 2020
Widely used
Mockoon · since 2017
Strengths
- One set of handlers reused across unit, component, E2E and local development.
- Application code is completely unaware it is being mocked — no test-only branches.
- Supports REST and GraphQL with the same model.
- Genuinely a minute from download to a working mock API.
- Dynamic templating with faker-style helpers produces realistic responses.
- Proxy mode mocks only the routes you need and passes the rest through.
Limitations
- JavaScript ecosystem only.
- Service Worker registration adds a setup step and occasional caching confusion.
- Handlers can drift from the real API without contract verification.
- Desktop-first; sharing mocks across a team needs the paid cloud or a committed config file.
- HTTP only.
- Less suited to complex stateful behaviour than WireMock.
Best for
Front-end teams that want one mocking approach across every kind of test.
Front-end developers unblocking themselves while a backend is still being built.
Pricing last reviewed August 2026 and is indicative only — confirm on each vendor’s own page.