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Tool 61 of 100 · Data

Mock Data Generator

Describe your fields and get hundreds of realistic, invented rows for prototypes, tests and demos, the same every time you use the same seed.

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Mock Data Generator at a glanceIllustration: 1, A field list; 2, processed in your browser; 3, Realistic test data.Mock Data Generator1A field list3Realistic test data2In yourbrowser
1 A field list 2 processed on your device 3 Realistic test data

Mock Data Generator

Fields

All field types

sequence [start step], uuid, firstName, lastName, fullName, email [domain], username, phone, street, city, postcode, country, company, jobTitle, int [min max], age [min max], float [min max dp], price [min max], bool [chance], date [from to], datetime [from to], time, ipv4, ipv6, mac, url, slug, word, words [n], sentence, paragraph, enum a|b*3|c, status, hexColor, currency, iban, lat, lng, constant text.

Output

Mock data

Preview (first 8 rows)

Phone numbers use Ofcom's drama range (07700 900xxx), IP addresses use documentation ranges and emails use example domains, so nothing reaches a real person.

01

What it does

Generates realistic fake rows from a field list, repeatable with a seed, as JSON, CSV, NDJSON or SQL INSERT statements.

  • Over 40 field types: names, emails, UK postcodes, prices and dates
  • Ranges, choices, patterns and nullable fields
  • Seeded, so the same settings give the same data
  • Up to 10,000 rows

02

Private by design

Everything happens in your browser. Nothing you type, paste or upload is sent anywhere, and it keeps working offline once the page has loaded.

03

What you get

JSON, CSV, NDJSON or SQL, with a Copy and a Download button on every result.

  • Test data
  • JSON
  • SQL
  • CSV

Why it matters

Designs and prototypes look wrong with 'Lorem ipsum' and 'Test User 1'. Real customer data is worse: it's personal data, and putting it in a test system is a GDPR problem.

This generator makes believable but invented data: names, emails on reserved example domains, UK addresses and postcodes, prices and dates in ranges you choose. A seed makes it repeatable, so tests and screenshots stay the same between runs.

How it works

  1. InputField names and types
  2. In your browserGenerated from a seed, so it repeats
  3. OutputJSON, CSV, SQL INSERTs or NDJSON

Where it fits in a designer's workflow

  1. Plan
  2. Design
  3. Build
  4. Test
  5. Launch
Seeding databases, demos and tests.

By the numbers

100 rows of the sample 11-field schema in each formatJSON: 35.3 KB; NDJSON: 28.3 KB; CSV: 17.1 KB; SQL INSERT: 20.5 KBJSON35.3 KBNDJSON28.3 KBCSV17.1 KBSQL INSERT20.5 KB
Generated by this tool with seed 1, so the same seed always gives the same rows. CSV is smallest because it writes the field names once; JSON repeats them on every row. Source: RFC 4180: CSV.
Show the numbers as a table
FormatBytes
JSON36174
NDJSON28971
CSV17506
SQL INSERT20986

How to use it

  1. Write one field per line as name: type options, for example age: int 18 90.
  2. Set the number of rows and a seed.
  3. Check the preview.
  4. Download as JSON, CSV, NDJSON or SQL.

FAQ

Are any of the people real?

No. Names are combined at random from common first names and surnames, and emails use example domains that can't receive mail.

Why use a seed?

The same seed and fields always give the same rows, so tests, screenshots and demos are repeatable.

Can I make the SQL for my database?

Yes. Give the table name; the INSERTs use standard SQL that works in PostgreSQL, MySQL and SQLite.

Is anything sent to a server?

No. The data is generated in your browser.

Work with me

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