Local REST API Response Mocker is a free, browser-based tool for frontend developers who need a quick fake backend. Define your routes and responses, and get a ready-to-run Express server file.
How to use the Local REST API Response Mocker
- Edit the routes JSON array — method, path, status code and response body for each route.
- Click Generate mock server.
- Download the generated mock-server.js file.
- Run `npm install express` then `node mock-server.js` to start it locally on port 4000.
Why use FreeToolsNets's Local REST API Response Mocker?
- 100% free, with no usage limits and no account required.
- Everything runs locally in your browser — nothing you type is uploaded or stored on a server.
- Works on desktop, tablet and mobile in any modern browser.
- No installation, no plugins, and no ads blocking the tool itself.
Frequently asked questions
Does this run in my browser?
No — this generates real Node.js/Express code for you to run locally; the code itself isn't executed in-browser.
Can I add request-based logic?
The generated code is a starting point — edit the handler functions directly for conditional responses, delays, or request validation.
Is this tool free to use?
Yes, completely free on FreeToolsNets, with no sign-up and no limits.
Is my data sent to a server?
No. Everything runs locally in your browser using JavaScript — nothing you enter is uploaded anywhere.
Does it work on mobile?
Yes, the widget is fully responsive and works on phones, tablets and desktops.