A seed you can return to
Keep the schema, row counts, field order, and seed unchanged to reproduce the same dataset in this version. This generator is not cryptographic.
THE SYNTHETIC DATA WORKBENCH
Synthetic test data.
Made in your browser.
Seedloom is a free synthetic test data generator for prototypes, tests, and demos. Set a schema and seed, link tables, then export repeatable CSV, JSON or SQLite SQL without uploading a dataset.
→ Up to 50,000 rows⌘ 10 field types⇄ Linked tables↓ CSV · JSON · SQL
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Shape your data
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No dataset yetInspect & export
A little structure goes a long way.
Your first 30 rows will appear here after generation.
CSV nulls are empty cells. JSON keeps nulls and types. CSV safety also escapes headers and negative numbers; turn it off only for a trusted non-spreadsheet importer. SQL creates new tables; review before running.
SMALL TOOL. CLEAR BOUNDARIES.
Test the shape.
Keep people out of it.
Your browser does the work
No generator API, accounts, runtime CDNs, or dataset uploads. The hosting service serves the page and may keep standard access logs.
Fixtures, not identities
Names are assembled from small example lists; emails use the reserved example.test domain. Coincidental name matches are possible. This is not an anonymization service.
Just the useful core
Finite unique fields must have enough choices. Links point to earlier tables only. No realistic locale datasets, hosted API, enrichment, or automatic sharing.
FREE TO USE · OPTIONAL TO SUPPORT
Help good tools grow.
Every feature works without a donation. If Seedloom saves you time, you can support its upkeep.
Open the crypto toolkit →BitcoinBTC · Bitcoin mainnet
bc1qz50cp2uwpp98hdv49ellhwatdm997yzm9xlh7hEthereumNative ETH · Ethereum mainnet
0x83604D79dF4ED54E8D8935def21a79B51798cDa5TetherUSDT · Ethereum / ERC-20
0x83604D79dF4ED54E8D8935def21a79B51798cDa5Check both the asset and network before sending. Transfers are generally irreversible. No wallet connection is used.