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New: OpenAPI 3.1 Support

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The fastest way to prototype your application. Create custom endpoints instantly with dynamic data and zero configuration.

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mock-api — http
❯curl -s https://api.mock.io/v1/users
HTTP/1.1 200 OK
Content-Type: application/json
X-Response-Time: 12ms
[
{ "id": 1, "name": "Jane Doe", "role": "Admin" },
{ "id": 2, "name": "Alex Kim" }
]
❯curl -X POST .../users -d '{"name":"New User"}'
HTTP/1.1 201 Created — 8ms
Live endpoint
api.mock.io/v1/users

Everything you need to ship faster

Stop waiting on backend teams. Mock your APIs, iterate freely, and deploy in under 60 seconds.

Instant Endpoints

Your endpoints go live the moment you save. No build step, no waiting — just a URL ready to use.

Dynamic Data Generation

Realistic fake data seeded per request — names, emails, UUIDs, dates — all configurable per field.

OpenAPI Import / Export

Paste a Swagger or OpenAPI 3.1 spec and we generate all endpoints automatically. Export back anytime.

Team Collaboration

Invite teammates, share projects, and keep everyone in sync with live access controls.

Up and running in 3 steps

No backend. No setup. Just your API.

1

Define your schema

Describe your endpoints and data shapes — manually or by importing an OpenAPI spec.

2

Get instant endpoints

We provision your mock server immediately. Every endpoint is live and returns realistic data.

3

Ship faster

Point your frontend at the mock URL. Build, test, and iterate without waiting on anyone.

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