Instant In-Browser Mock API Generator
Build and test frontend features before backend APIs are ready. Generate dynamic faker schemas, simulate 500 error responses, and test slow 3G latency with zero configuration.
{
"status": "success",
"data": {
"userId": "usr_982f1b0a",
"name": "Sarah Jenkins",
"email": "s.jenkins@enterprise.io",
"role": "Engineering Lead",
"billingPlan": "Enterprise_Annual"
},
"metadata": {
"responseLatencyMs": 180,
"serverRegion": "in-browser-worker"
}
}Core Mocking Capabilities
🎲 Dynamic Faker Engine
Generate realistic names, emails, credit cards, dates, and addresses automatically on every simulated request.
⏱️ Latency & Throttling
Test UI loading spinners and skeleton loaders by simulating 200ms, 1000ms, or variable mobile network delays.
💥 Chaos & Error Simulation
Trigger 400 Bad Request, 401 Unauthorized, 429 Rate Limited, and 500 Internal Server Errors to verify error handling.
🌐 Zero Backend Needed
Runs 100% inside your browser. No Express server to spin up, no Docker containers, and no external subscriptions.
Frequently Asked Questions
How does in-browser mock API generation work?
APIFlow Studio uses client-side interception. When you click Send or run a test flow, our mock runner matches your path, applies your faker templates, and returns synthetic JSON responses in milliseconds without network round-trips.
Can I export my mocks to OpenAPI?
Yes! With one click, export all your mock contracts and schema definitions into valid OpenAPI 3.1 or Postman Collection v2.1 files to share with backend engineers.
Start Mocking APIs in Seconds
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