Generate JSON Test Data for an API

Build realistic JSON payloads for testing endpoints and mock servers.

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Fields

5 columns

Rows

Format

💡 All data is randomly generated in your browser — no rows limit, no account, nothing uploaded. Names, companies, and addresses are fictional and any resemblance to real data is coincidental.

API testing tips

📦

Use the JSON format for an array of objects you can paste straight into a mock server or test fixture.

🧱

NDJSON (newline-delimited) is ideal for streaming endpoints and bulk-import tools like Elasticsearch.

🏷️

Name your fields to match your API schema exactly, then regenerate as many records as you need.

🔒

No data leaves your browser — safe for prototyping against internal API contracts.

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Ewch i mewn

Enter your data into the tool above. Everything stays local to your browser.

Proses

The tool processes your data instantly in your browser using JavaScript. No server, no waiting.

Lawrlwythwch

Get your result instantly. Nothing is stored after you leave the page — complete privacy.

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