Generate realistic, made-up test data
Testing a Japanese form with “John Smith, 123 Main St” misses the real problems: names in kanji, 〒 postal codes, full-width digits. This tool generates made-up data shaped like real Japanese data.
- Runs entirely in your browser
- Works offline
- No upload
- No sign-up
- No watermark
Loading the tool…
How it works
- Choose the columns and what each one holds — or start from the ready-made set.
- Choose how many rows.
- Generate, preview, and download as CSV or JSON.
Why nothing is uploaded
Every operation on this page is done by code running inside your browser tab, using the same engine that renders web pages. The file is read from disk into your tab’s memory, transformed there, and written back out as a download. It is never sent anywhere — not to us, not to a third party.
Verify it yourself
- Open your browser’s developer tools (F12) and select the Network tab.
- Load your file and run the tool.
- The only requests you will see fetch the tool’s own code — and, for a few heavy tools, their open-source engine from a public CDN — plus one small page-view ping to loreatec.jp (page address and title, nothing more). None of them carry your file.
Frequently asked questions
Is any of this real personal data?
No. Names are put together from lists of common surnames and given names; addresses use real prefecture and ward names with invented block numbers; phone numbers and emails are plausible-looking but arbitrary, on example domains. Realistic shape, zero real people.
Why do I need Japanese-shaped test data?
Because the problems are specific to Japanese data: a name field built for the Latin alphabet cuts 渡辺 short, a form check rejects 〒150-0002, a CSV import breaks on Japanese characters. Test data shaped like your real data finds these problems before your real users do.
Can I add my own value list?
Yes. The “pick from list” type takes values separated by commas and picks one at random for each row. That covers status columns, categories, plans and any other fixed set of options.
Is the data random every time?
Yes, it is drawn fresh each time you generate. If you need the same data set every time for repeatable tests, generate it once and save the CSV in your project. A saved file cannot drift, so that beats any “seed” option.