Mocksy app icon

Mock faster

Stop Waiting for APIs. Mock Them in Seconds on Your Mac.

Mocksy lets macOS developers spin up a focused local server with intuitive controls so you can prototype flows, simulate edge cases, and keep building even when production services are unavailable.

Download on the Mac App Store
(It's free to get started)
Explore features

“Finally, a tool that doesn't feel like an Electron bloatware. Native, fast, and does exactly what it says. Saved me hours on my last sprint.”

Alex D.
Alex D. iOS Developer at FinTech Co.

“The ability to switch scenarios instantly is a game changer. I no longer wait for the backend team to deploy. It just works.”

S
Sarah M. Full Stack Engineer

Designed for deep work

Bring realism to your local development environment with customizable endpoints, real-time monitoring, and a streamlined local server that mirrors production behavior.

Local server workspace

Launch a dedicated mock server per project with zero terminal setup and keep it focused on the scenario you are iterating on.

Real-time monitoring

Inspect incoming requests and responses instantly so you can troubleshoot payloads, headers, and status codes without leaving the app.

Custom responses

Design JSON or text bodies, set headers, and craft status codes to emulate the exact behavior your client expects.

Inspect what ships

Track every request as it hits your local server, replay payloads, and quickly iterate on endpoint definitions without restarting your workflow.

macOS 13+ Apple Silicon & Intel Offline friendly
Mocksy example response editor screenshot

Craft responses, save reusable templates, and jump between scenarios without touching your production backend.

See Mocksy in action

Every view is tuned for clarity—from high-level endpoint overviews to granular response editors.

Mocksy live Inspector overview Inspect every request with live logs and response previews.
Mocksy response details panel Drill into headers, payloads, and timings to match production behavior.
Mocksy JSON response editor Shape responses with a focused JSON editor and instant validation.

Mocksy Pro (coming soon)

We are building Mocksy Pro for power users. Get early access updates and help shape advanced workflows tailored for larger teams.

Multiple servers

Run and manage several mock servers at once with isolated configs per feature branch.

Proxy mode

Forward requests to live services when needed and intercept or reshape responses on the fly.

Dynamic scripts & export

Add logic to responses and export/import endpoint libraries to share with your team.

FAQs

Does Mocksy replace my backend?

No. Mocksy augments your workflow so you can simulate services when real endpoints are unstable or unavailable.

Will my mocks sync across devices?

Mocksy stores configurations locally on your Mac today. Multi-device sync will be evaluated after Mocksy Pro launches.

Can I use Mocksy offline?

Absolutely. Mocksy keeps serving local responses even when you disconnect from the internet.