Snaplet Seed vs Mockaroo

Free and open source

From $60 per year (indicative, Silver)

The Seed library is open source and free; note that Snaplet wound down its hosted product, so treat this as a library rather than a service.

Cheap for what it does; higher tiers raise row limits and add API quota.

Everything, self-hosted

Free for up to 1,000 rows per download and a limited number of saved schemas.

Emerging

Snaplet · since 2021

Established

Mockaroo LLC · since 2014

• Schema-aware generation means the data actually inserts and the app actually works.
• Deterministic seeds make failing tests reproducible.
• Good TypeScript ergonomics with Prisma and Drizzle.

• No code required — an analyst or tester can design a dataset themselves.
• Very large library of realistic field types including regional formats.
• Formula fields allow simple business rules between columns.

• The company wound down its hosted business — evaluate the library's maintenance status before depending on it.
• PostgreSQL-centric.
• TypeScript ecosystem only.

• Referential integrity across related tables is limited.
• Free-tier row limits are low for realistic volume testing.
• Data is generated on a third-party service, which needs a privacy check for schema sensitivity.

TypeScript teams that want each developer and CI run to start from a clean, coherent database.

Quickly producing a realistic dataset for a demo, a load test or a new environment.