Playground API offers zero-config mock REST API with real session-based data persistence

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A developer has launched Playground API, a free mock REST API tool designed for frontend developers, QA engineers, and prototypers. Unlike standard mock services such as JSONPlaceholder, it actually persists CRUD operations — meaning created, updated, or deleted records are reflected in subsequent GET requests. The tool requires no account registration, API keys, or local server setup, and comes preloaded with baseline datasets including users, posts, comments, and todos. Each user gets an isolated session, preventing data conflicts between developers. A built-in browser request tester is also included, removing the need for external tools like Postman.

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