just/mocks_
mockzilla.org →
Hosted mock APIs · free · no signup

Mock APIs.
No setup.

Free, hosted mocks of the third-party APIs you build against: Stripe, HSBC, Vipps, and more. No signup. No setup. No SDK. Just a URL that returns the response shape, generated straight from the provider's OpenAPI spec.

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Featured mocks

popular this week
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Powered by mockzilla

open source · cloud · free tier

Mock APIs, generated from OpenAPI specs.

mockzilla is an open-source mock server. Point it at an OpenAPI spec and it serves realistic responses for every endpoint: correct schemas, correct status codes, correct content types. It runs anywhere a binary or Docker container runs.

mockzilla.org is the hosted version. Push your OpenAPI spec to GitHub, get a private simulation URL in seconds. PR environments, multi-region deploy, rate-limit headers, optional API keys. The free tier covers one repo, ten thousand requests a month, no credit card.

justmocks is this public catalog: pre-built mocks of third-party services (Stripe, HSBC, Vipps, and growing), running on the same mockzilla engine. Free for anyone to curl, no signup required.

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How it works

spec → runtime → catalog → access
01 / SPEC

Provider publishes an OpenAPI spec.

We grab it untouched. No hand-written stubs, no AI-generated fixtures.

02 / RUNTIME

mockzilla generates the simulation.

Every endpoint, status code, schema. Responses match the contract field-for-field.

03 / CATALOG

Listed on justmocks.

Each mock gets its own page with the full endpoint list, the live URL, and a link to the source OpenAPI spec.

04 / ACCESS

You hit the URL.

No signup. No key. Just a hostname that returns the shape.

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Questions

frequently filed

FAQ.

Still confused? Email info@justmocks.com.

01Are these real APIs? +
No. Each mock is served from api.justmocks.com/<slug>/… and returns synthetic responses generated from the provider's OpenAPI spec. They look real, but they don't move money, talk to your bank, or trigger webhooks at the real provider.
02How do you generate the responses? +
Straight from the provider's published OpenAPI spec. Every field, status code, and content type defined in the spec is honored. The mockzilla engine reads the schema and returns a valid example shape. It's the same engine that powers private team simulations on mockzilla.org.
03Who runs justmocks? +
The team behind mockzilla.org. justmocks is the free, public, search-indexed catalog. mockzilla.org is the platform: push your own OpenAPI spec to GitHub, get a private simulation URL.
04Can I request a mock for $service? +
Yes, if the provider publishes an OpenAPI spec, we can add it. Email info@justmocks.com with the spec URL or use the contact form on mockzilla.org.
05Will this stay free? +
Yes. The public catalog stays free, no signup, no key. Private, persistent mocks of your own OpenAPI spec, with PR environments, team seats, and a GitHub Action, are what mockzilla.org is for.