Mock API platform

OpenAPI mock serverPoint it at a spec and every path answers.Hosted mock serverOne stable URL, close to the team calling it.Latency and errorsMake it slow, make it fail, see what breaks.API proxyProxy the real API, mock what is missing.

PR environmentsA mock server for every pull request.History and replayEvery request kept, any of them replayed.Fake JSON APIServe your own JSON files on a real URL.All featuresEverything the mock server does.

Resilient Backends

OverviewProvider APIs, rebuilt for testing.Payment backendsAuthorisations, refunds, 3DS and decline codes.Identity: KYC and KYBDocument checks, screening and applicant flows.Self-hostedThe same providers, inside your own network.

Install the CLI GitHub Action MCP server GitHub

Learn

ArticlesGuides, comparisons and product writing.For studentsFree while you are studying.ContactAsk about a plan or a provider.

Open source

Mock server enginemockzilla GitHub Actionactions MCP servermockzilla-mcp Server templatesmockzilla-portable-template All repositories

Featured reading

Mockoon alternative: keep your mock API in sync with your OpenAPI spec Stoplight Prism alternative: an OpenAPI mock server with a URL WireMock alternative: mock an OpenAPI spec without writing stubs All articles

Mock API platform

Mock API plansFree to start, then monthly or yearly.Custom planSet your own limits and see the price.

Resilient Backends

Hosted backendsPriced per provider, on top of your plan.Self-hosted backendsPriced per provider. No plan needed.

Free for students Contact sales

Getting started

What Mockzilla is, core concepts, and your first simulation.

What is Mockzilla?Mockzilla is an MIT-licensed open source mock server for OpenAPI specs. The cloud platform at mockzilla.org builds and deploys mock servers for teams, free for small teams and students.Updated Sep 29, 2026 TerminologyWhat Mockzilla's terms mean and why we chose them: simulations, specs, services, replays, contexts, scenarios, resilient backends and more.Updated Sep 29, 2026 Install the CLIHow to install the Mockzilla CLI with Homebrew or a prebuilt binary, and when you need it at all.Updated Sep 29, 2026 Quickstart: your first simulationCreate a sample simulation in the browser, deploy it, and call your hosted mock API in a few minutes.Updated Sep 29, 2026