Mock Data Generator

Q: Does the same seed always produce the same data?

Yes. Generation uses a seeded pseudo-random generator, so the same schema and seed always produce byte-for-byte identical rows — useful for reproducible test fixtures across runs or machines.

Q: Can I generate realistic-looking payment card numbers?

No — this tool intentionally does not include a credit-card-number generator. An algorithmically valid-looking card number can be mistaken for a usable payment credential, which this tool avoids implying.

Q: What does "unique (best-effort)" mean?

The generator retries up to 50 times to avoid a duplicate value for that field. For naturally large domains (UUID, email) this is effectively always unique; for small domains (e.g. a boolean or a 2-value enum) with a large row count, duplicates may still occur — a warning is shown when that happens.

Q: Is my schema or generated data uploaded anywhere?

No. Everything — the schema you design and the rows it produces — is generated and rendered entirely in your browser. Nothing is sent to a server, added to the URL, or saved automatically.

Q: How many rows can I generate?

Row count is capped at 5,000 in this tool to keep generation and the export textarea responsive in a browser tab.

Define a schema of fields, pick a row count and a seed, and generate mock data entirely in your browser. Regenerating with the same schema and seed always produces the exact same rows, so fixtures are reproducible. Nothing is uploaded; you can optionally save your schema locally as a workspace.

Row count

Capped at 5,000 rows for a browser tab

Seed

Same seed + schema = same output

SQL table name

Preview (first 10 of 25 rows)

id	name	email	signedUpAt	plan	isActive
838f84bd-4664-4c76-b4a0-75766fb5b8bc	Logan Wilson	logan.jackson424@example.org	2028-01-02T07:52:39.502Z	free	false
f9fd757b-e43f-47da-9776-8f988e1e51b9	Ava Taylor	ava.lopez708@example.org	2017-05-05T21:18:36.878Z	free	true
d8367362-37af-443d-a036-c457fd402d9a	Olivia Moore	david.allen269@example.com	2016-07-12T04:59:31.347Z	free	false
3bd04042-3a84-43be-92a2-e958fa8bc3e3	Emma Young	evelyn.johnson247@example.org	2026-01-23T22:11:09.196Z	enterprise	false
554cd3ce-e0dd-4736-9c38-388941a0a1db	Joseph White	charlotte.wilson131@example.com	2026-02-19T02:14:59.813Z	enterprise	true
df03e134-d926-481b-92a0-3c79ec8ae086	Daniel Jackson	benjamin.martin413@example.net	2028-04-11T23:07:25.173Z	pro	false
27dd1b12-38c1-4bb7-983d-98fb0e361525	Lucas Lopez	sophia.miller373@example.com	2020-09-21T16:50:04.158Z	enterprise	false
5f9113e6-ec3f-45a9-b464-11bd553fc6ac	Evelyn White	ethan.martinez426@example.org	2026-12-26T08:20:07.216Z	free	false
02c3d077-1ae3-461f-8861-532441dce9e5	Mason Martin	isabella.clark473@example.com	2017-10-24T05:07:10.828Z	free	true
2430b35c-afc1-4a5c-9a80-3d1b3a73975c	David Thompson	ethan.walker50@example.net	2024-05-09T10:54:41.902Z	free	false

[
  {
    "id": "838f84bd-4664-4c76-b4a0-75766fb5b8bc",
    "name": "Logan Wilson",
    "email": "logan.jackson424@example.org",
    "signedUpAt": "2028-01-02T07:52:39.502Z",
    "plan": "free",
    "isActive": false
  },
  {
    "id": "f9fd757b-e43f-47da-9776-8f988e1e51b9",
    "name": "Ava Taylor",
    "email": "ava.lopez708@example.org",
    "signedUpAt": "2017-05-05T21:18:36.878Z",
    "plan": "free",
    "isActive": true
  },
  {
    "id": "d8367362-37af-443d-a036-c457fd402d9a",
    "name": "Olivia Moore",
    "email": "david.allen269@example.com",
    "signedUpAt": "2016-07-12T04:59:31.347Z",
    "plan": "free",
    "isActive": false
  },
  {
    "id": "3bd04042-3a84-43be-92a2-e958fa8bc3e3",
    "name": "Emma Young",
    "email": "evelyn.johnson247@example.org",
    "signedUpAt": "2026-01-23T22:11:09.196Z",
    "plan": "enterprise",
    "isActive": false
  },
  {
    "id": "554cd3ce-e0dd-4736-9c38-388941a0a1db",
    "name": "Joseph White",
    "email": "charlotte.wilson131@example.com",
    "signedUpAt": "2026-02-19T02:14:59.813Z",
    "plan": "enterprise",
    "isActive": true
  },
  {
    "id": "df03e134-d926-481b-92a0-3c79ec8ae086",
    "name": "Daniel Jackson",
    "email": "benjamin.martin413@example.net",
    "signedUpAt": "2028-04-11T23:07:25.173Z",
    "plan": "pro",
    "isActive": false
  },
  {
    "id": "27dd1b12-38c1-4bb7-983d-98fb0e361525",
    "name": "Lucas Lopez",
    "email": "sophia.miller373@example.com",
    "signedUpAt": "2020-09-21T16:50:04.158Z",
    "plan": "enterprise",
    "isActive": false
  },
  {
    "id": "5f9113e6-ec3f-45a9-b464-11bd553fc6ac",
    "name": "Evelyn White",
    "email": "ethan.martinez426@example.org",
    "signedUpAt": "2026-12-26T08:20:07.216Z",
    "plan": "free",
    "isActive": false
  },
  {
    "id": "02c3d077-1ae3-461f-8861-532441dce9e5",
    "name": "Mason Martin",
    "email": "isabella.clark473@example.com",
    "signedUpAt": "2017-10-24T05:07:10.828Z",
    "plan": "free",
    "isActive": true
  },
  {
    "id": "2430b35c-afc1-4a5c-9a80-3d1b3a73975c",
    "name": "David Thompson",
    "email": "ethan.walker50@example.net",
    "signedUpAt": "2024-05-09T10:54:41.902Z",
    "plan": "free",
    "isActive": false
  },
  {
    "id": "f2994384-7226-4712-ab0f-0c1404258892",
    "name": "Lucas Rodriguez",
    "email": "riley.rodriguez314@example.org",
    "signedUpAt": "2020-11-16T22:31:40.493Z",
    "plan": "free",
    "isActive": true
  },
  {
    "id": "b06b6bb7-dcc9-4769-98a3-9a1aada4e491",
    "name": "Charlotte Harris",
    "email": "aria.moore252@example.org",
    "signedUpAt": "2026-04-30T21:15:56.829Z",
    "plan": "enterprise",
    "isActive": true
  },
  {
    "id": "30379af7-056a-426f-95a2-8c9718a1942e",
    "name": "Ava Wilson",
    "email": "logan.perez88@example.org",
    "signedUpAt": "2015-03-01T20:27:50.825Z",
    "plan": "enterprise",
    "isActive": false
  },
  {
    "id": "2df90c0a-5f72-400c-918e-4586adaea766",
    "name": "Charlotte Davis",
    "email": "daniel.scott679@example.com",
    "signedUpAt": "2023-09-25T12:41:00.154Z",
    "plan": "free",
    "isActive": false
  },
  {
    "id": "3b423346-33e1-43b9-96c6-06898ee6f723",
    "name": "Daniel Moore",
    "email": "abigail.wright248@example.net",
    "signedUpAt": "2015-12-05T23:24:08.112Z",
    "plan": "enterprise",
    "isActive": false
  },
  {
    "id": "61a7138b-f2bd-4f22-9b0c-dedf101c5407",
    "name": "Matthew Clark",
    "email": "chloe.lewis835@example.org",
    "signedUpAt": "2016-06-17T09:15:06.741Z",
    "plan": "pro",
    "isActive": true
  },
  {
    "id": "2b98b742-78d2-4aa5-bdf0-d85599c60f45",
    "name": "Abigail Walker",
    "email": "ava.garcia572@example.com",
    "signedUpAt": "2026-04-17T01:27:55.948Z",
    "plan": "enterprise",
    "isActive": true
  },
  {
    "id": "e8dc1101-7844-4500-a665-75abe3c6264b",
    "name": "Mia Lopez",
    "email": "evelyn.king984@example.org",
    "signedUpAt": "2028-09-07T20:03:13.520Z",
    "plan": "pro",
    "isActive": false
  },
  {
    "id": "b6b4cd15-f097-40a9-895b-d1bfcfa304c7",
    "name": "Matthew Scott",
    "email": "grace.martin119@example.com",
    "signedUpAt": "2020-01-27T01:59:15.520Z",
    "plan": "pro",
    "isActive": false
  },
  {
    "id": "a07c806d-c5f4-4358-a207-5456d768c80d",
    "name": "Emma Martin",
    "email": "harper.scott769@example.net",
    "signedUpAt": "2026-04-30T15:58:56.833Z",
    "plan": "pro",
    "isActive": false
  },
  {
    "id": "d85a1359-7515-4a42-a9ea-f5a96e0de161",
    "name": "Daniel Scott",
    "email": "ethan.lewis230@example.net",
    "signedUpAt": "2026-11-10T15:35:12.546Z",
    "plan": "enterprise",
    "isActive": true
  },
  {
    "id": "129e1dfe-48d1-4249-863b-9ee243823327",
    "name": "Noah Moore",
    "email": "ava.harris846@example.org",
    "signedUpAt": "2028-01-14T13:04:11.549Z",
    "plan": "enterprise",
    "isActive": false
  },
  {
    "id": "143c2a7b-6ac0-449b-a694-8577f90cd7b0",
    "name": "Ethan Thompson",
    "email": "james.garcia764@example.net",
    "signedUpAt": "2025-08-01T04:05:08.194Z",
    "plan": "enterprise",
    "isActive": false
  },
  {
    "id": "5bfd0d2f-8fb1-4149-bb86-47e072d610cb",
    "name": "Riley Lee",
    "email": "samuel.king229@example.org",
    "signedUpAt": "2017-05-22T19:14:52.939Z",
    "plan": "free",
    "isActive": true
  },
  {
    "id": "685cf263-b7f2-45af-a6b3-9f612b5db0f2",
    "name": "Emma White",
    "email": "amelia.lewis989@example.com",
    "signedUpAt": "2023-08-26T05:39:00.510Z",
    "plan": "enterprise",
    "isActive": false
  }
]

Mock Data Generator

FAQ

Does the same seed always produce the same data?

Can I generate realistic-looking payment card numbers?

What does "unique (best-effort)" mean?

Is my schema or generated data uploaded anywhere?

How many rows can I generate?