API Mockup Creator
Define mock API endpoints and generate JSON responses instantly.
Free Web vs Desktop App
Web (Free)
- +API Mockup Creator with basic functionality
- +No signup or account required
- +Works in any modern browser
- -Up to 5 endpoints on the web
- -Single tool per page, no integrations
Desktop App ($29 one-time)
- Unlimited endpoints, local mock server, integrated with HTTP client
- All 19 developer utilities in one ToolBox
- Plus terminal, HTTP client, database client, Docker manager
- AI agents, code editor, Git client, and 100+ more features
- macOS, Windows, Linux — one-time purchase, own forever
About API Mockup Creator
Design mock API endpoints by defining routes, methods, status codes, and JSON response bodies. Generate a shareable mock configuration and preview responses. Perfect for frontend developers who need to work against an API before the backend is ready, for prototyping, and for documentation.
Frequently Asked Questions
Is API Mockup Creator free to use?
Yes! This online version is completely free with no signup required. Up to 5 endpoints on the web. For unlimited usage and full integration with 100+ developer tools, download the 1DevTool desktop app ($29 one-time).
Is my data safe?
Absolutely. All processing happens entirely in your browser. Your data never leaves your machine — nothing is sent to any server. The tool runs 100% client-side using JavaScript.
What do I get with the desktop app?
The desktop app includes API Mockup Creator with no limits, plus 18 other developer utilities. Beyond the ToolBox, you get multi-agent AI terminals, HTTP client, database client (26 engines), Docker manager, Git client, code editor, browser preview, and more — all in one workspace. $29 one-time, no subscription.
Like this tool? There's a lot more.
Download 1DevTool to get API Mockup Creator with no limits, plus 18 other utilities, AI terminals, HTTP client, database client, and 100+ features.