JSONing
JSONing is a free, open-source mock/fake API generator and JSON toolkit (formatter, validator, JSONPath, mock rules) for testing and prototyping. · JSONing · Storage
Overview
JSONing provides a free, open-source mock/fake API generator plus JSON utility tools (formatter, validator, JSONPath, and more). Custom mock APIs are live instantly with no signup, but their data is wiped once a day — great for prototyping and testing, not for real data persistence. The source is on GitHub for anyone who wants a permanent, self-hosted copy.
Good fit
Use JSONing when you need a fast, free fake API for prototyping or testing without writing or hosting a real backend.
- prototyping
- hackathons
- student projects
- frontend development without a backend
Not a fit
Avoid if you need persistent, production-grade, or long-lived data storage — hosted custom APIs are wiped once a day.
- handling sensitive data
- requiring high availability
- needing persistent storage
Quickstart · 5 steps
- Visit jsoning.com/api and open the Mock API / Custom API tool.
- Define your JSON resources (arrays of objects) in the editor.
- Optionally add rules to customize status codes, headers, or bodies.
- Use the generated endpoint immediately — no signup required.
- Recreate it after it is deleted, or self-host the open-source API for permanence.