New — Realtime WebSocket Mocking is here

Debug Webhooks.
Mock APIs.
Ship Faster.

MockLab gives your team instant webhook inspection, mock REST endpoints, and WebSocket servers — everything you need to build without a real backend.

Free forever · No credit card required · Up in 30 seconds

app.mocklab.dev
MockLab
Webhook Inspector
Incoming Requests
Live
POST /webhook/stripe-events 12:41:03
POST /webhook/github-push 12:40:58
POST /webhook/sendgrid-bounce 12:40:51
Request Body
{
  "event": "payment.completed",
  "id": "evt_3Pxr...",
  "amount": 4999,
  "currency": "usd",
  "customer": "cus_Qx..."
}

Just launched

MockLab is brand new and building in public. Be among the first developers to try it — sign up free and help shape what we build next.

Catch every payload.
Debug in seconds.

Get a permanent HTTPS endpoint. Every POST, PUT, or GET is captured instantly — full headers, raw body, query params, and timing. No setup, no infrastructure.

  • Real-time request inspection
  • One-click request replay
  • Custom routing rules
  • Signature verification helpers
Explore Webhook Inspector →
Incoming Requests · Live
POST /wh/stripe-events just now
{"event":"payment.completed","amount":4999} payment.completed
POST /wh/github 2s ago
{"ref":"refs/heads/main","pusher":{"name":"dev"}} push
POST /wh/sendgrid-bounce 8s ago
{"event":"bounce","email":"[email protected]"} bounce

Public REST endpoints.
Zero backend needed.

Create a mock collection and get a fully functional REST API in seconds. Auto-generated realistic data, configurable schema, and full CRUD support — import your OpenAPI spec and you're done.

  • Full CRUD — GET, POST, PUT, PATCH, DELETE
  • Auto-generated realistic data
  • Import from OpenAPI / Swagger
  • Persistent data on Pro
Explore Mock REST API →
GET /m/user123/products 200 OK
[
  {
    "id": "prod_4kX9z",
    "name": "Wireless Headphones",
    "price": 79.99,
    "currency": "USD",
    "inStock": true,
    "category": "Electronics",
    "createdAt": "2024-03-12"
  },
  {
    "id": "prod_mR2qP",
    "name": "Standing Desk",
    "price": 449.00,
    "currency": "USD",
    "inStock": false,
    "category": "Furniture"
  }
]
GET /list POST /create PUT /:id DELETE /:id

Real-time testing.
No server required.

Spin up a WebSocket or Socket.io server in one click. Define events to broadcast, schedule automatic triggers, and watch live client connections from the dashboard. Test chaos scenarios like errors and slow responses without touching real code.

  • WebSocket & Socket.io support
  • Broadcast events to all clients
  • Automated event schedules
  • Error & slow-response scenarios
  • Live connection dashboard
Explore WS Mock →
my-app-ws
3 connected
Events
order:updated
broadcast · every 5s
price:tick
broadcast · every 1s
chat:message
→ client_3 · manual
Connection URL
wss://ws.mocklab.com/v1/my-app-ws

Loved by developers

Don't take our word for it.

"MockLab shaved days off every sprint. I can develop the frontend against a live webhook endpoint without waiting for the backend team."

Sarah K.
Senior Frontend Engineer

"The WebSocket mock is a game changer. We test real-time features in CI without any running backend. It just works."

Marcus T.
Staff Engineer

"Chaos testing with scenario modes helped us find three critical bugs in our error-handling logic before they hit production."

Priya M.
QA Lead
50K+
Developers
200M+
Requests mocked
99.9%
Uptime SLA

Simple, transparent pricing

Start free. Upgrade when you need more.

Free
Perfect for solo developers and side projects.
$0 /month
  • 1 webhook endpoint
  • 1 WebSocket project
  • 5 mock rules
  • 200 requests / day
  • Community support
Get Started Free
Popular
Pro
For professional developers who need more power.
$9 /month
  • Unlimited endpoints
  • 20 WebSocket projects
  • Unlimited mock rules
  • Unlimited requests
  • Persistent data
  • Request replay
  • Priority email support
Start Pro

Frequently asked questions

Have more questions? View the full FAQ →

What is MockLab?
MockLab is a developer platform for webhook debugging and API mocking. It gives you an instant HTTPS endpoint to receive webhooks, mock REST endpoints with auto-generated data, and WebSocket servers for real-time testing — all without a real backend.
Is it free to use?
Yes. The Free plan is permanent — no credit card required. You get one webhook endpoint, one WebSocket project, and 200 requests per day. Upgrade to Pro ($9/mo) when you need more.
Do I need to install anything?
No. MockLab is entirely browser-based. Sign up, get your endpoint URL, and start receiving webhooks in under 30 seconds.
How does webhook inspection work?
Every request sent to your MockLab endpoint is captured in real time. You can inspect headers, the full request body, query parameters, and timing. You can also replay any captured request with a single click.
Can I mock WebSocket connections?
Yes. MockLab's WS / Socket Mock feature lets you spin up a WebSocket or Socket.io server instantly. Define events to broadcast, set schedules to fire events on a repeating interval, and watch live client connections in real time.

Start in 30 seconds.
Ship the same day.

No credit card. No setup. Just sign up and get your webhook endpoint instantly.