04 / Testing / api-assertions

API Assertions

Assert status, body text and JSONPath values of API responses.

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04 · Workspace

How to use

  1. 01Open the API Assertions — it loads instantly with an example so you can see how it works.
  2. 02Paste or type your own input, or adjust the options above the output.
  3. 03Results update locally in your browser; invalid input shows a readable error.
  4. 04Copy the result or download it as a file when you are done.

What is this tool?

API Assertions is a free, browser-based Testing utility. Assert status, body text and JSONPath values of API responses. Everything runs client-side: nothing you enter is uploaded, stored or logged, which makes it safe for everyday QA and development work involving assert, api, test.

Common use cases

  • Quick testing checks while debugging
  • Preparing fixtures and examples for automated tests
  • Reviewing data from API responses and logs
  • Sharing reproducible snippets with teammates

FAQ

Is API Assertions free?

Yes. It is free, requires no signup and has no usage limits beyond your browser's memory.

Is my data uploaded?

No. Processing happens entirely in your browser tab and nothing is persisted.

What happens with invalid input?

The tool shows a readable error message instead of crashing, so you can fix the input and try again.