The Ultimate Algorithmic Mock Data Engine. Stop mocking with random strings — generate cryptographically valid test data. 390 types · 6 locales · Zero dependencies · CLI (Local Serverless) + REST API + Pyton LIb + JMeter Plugin.
Multi-protocol mock server for HTTP, gRPC, GraphQL, WebSocket, MQTT, SSE, and SOAP. One Go binary, zero dependencies. Supports stateful CRUD, digital twins (passes real SDK tests), chaos engineering, OpenAPI/Postman/HAR/cURL import, and a built-in MCP server for AI agents.
Cost / License
- Freemium
- Open Source (Apache-2.0)
Platforms
- Online
- Software as a Service (SaaS)
- Linux
- Windows
- Mac


Karate is the only open-source tool to combine API test-automation, mocks, performance-testing and even UI automation into a single, unified framework. The BDD syntax popularized by Cucumber is language-neutral, and easy for even non-programmers.


+1
Built from the ground up for mobile developers. Monitor network requests, logs, and events in real-time. Debug faster, ship with confidence.
Cost / License
- Paid
- Proprietary
Application type
Platforms
- Online
- Android
- iPhone
- iPad
- Software as a Service (SaaS)


+2
Free desktop API mocking platform. Create HTTP/REST and WebSocket mock servers with a modern UI. Perfect for developers, QA teams, and trainers.
Cost / License
- Free
- Proprietary
Platforms
- Mac
- Windows
- Linux

Instantly create HTTP mock API endpoints with custom responses, dynamic path params, custom headers, configurable delays, and real-time traffic logs.
Cost / License
- Free
- Proprietary
Platforms
- Online
- Self-Hosted


+2
Requex is a developer platform for webhook inspection, mock servers, and workflow automation. Capture, debug, and replay webhooks, connect one api to multiple apis, and automate API workflows - all from one dashboard.
Cost / License
- Free
- Proprietary
Platforms
- Online
- Software as a Service (SaaS)


+4
Cost / License
- Freemium
- Proprietary
Platforms
- Windows
- Mac
- Linux


+4






















