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API Mock Data Generator

Generate fake JSON or CSV test data from a template of tokens — names, emails, dates, UUIDs and more, with a reproducible seed.

🔒 Runs in your browser — files never leave your deviceFree · No sign-up

Record template

One JSON object describing a single record. Any token inside a string is replaced per record.

Output

Result

0Records
0 BSize

Token reference

Click a token to insert it into the template at the cursor.

How to generate mock data

  1. Write one JSON object that describes a single record and drop tokens such as {{ name }}, {{ email }} or {{ int 1 100 }} into the string values — or paste a real API response under “From sample JSON” and let the template be built for you.
  2. Set how many records you want, pick JSON or CSV, and press Generate. Keep the seed to reproduce exactly the same data later, or press “New seed” for a fresh batch.
  3. Copy the result or download it as .json / .csv for your tests, fixtures or database seed script.

FAQ

How do I get real numbers instead of strings?

When a string value is nothing but a single token — "{{ int 18 65 }}" — the result is written as a JSON number. Mix a token with other text, like "user-{{ index }}", and you get a string. The same rule applies to {{ bool }}, {{ float 0 1 }} and {{ timestamp }}.

Can I get the same data twice?

Yes. Every batch is produced by a seeded random generator, so re-running with the same seed, template and record count gives byte-identical output — handy for snapshot tests and shared fixtures.

Is the data sent anywhere?

No. The templates, the sample you paste and the generated records all stay in your browser; nothing is uploaded and no API is called.

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