Build a schema, generate realistic sample rows, and export them for development, testing and database seeding — free, with no sign-up.
SCHEMA is a free random data generator for developers and testers. You define the structure of your data — field names and their types — and the tool generates realistic rows for you. Unlike generic "Lorem ipsum" filler, it produces data that looks like the real thing: names, emails, phone numbers, cities, countries, UUIDs, dates, numbers and more. Everything runs in your browser, so even sensitive test schemas never leave your machine.
Building your dataset takes three steps:
Each type has sensible options: integers and floats accept a minimum and maximum range, dates accept a start and end range, and custom lists let you pass your own set of values to pick from.
Most generators only produce flat columns. SCHEMA also supports composite fields, so you can model structures that match real-world APIs and databases:
These nested structures are preserved when exporting to JSON and SQL, so you can test endpoints and schemas with data that actually fits your shape.
Frontend and backend developers who need mock data while the real database is still being built. QA engineers who need edge-case volumes of records to test pagination, search and export features. Anyone seeding a local development database for demos or tests. Data scientists preparing sample datasets without exposing real user information. Because the tool is offline-friendly, you can generate data anywhere, even without an internet connection after the page loads.
How many rows can I generate? Up to 50,000 rows per generation, with a live preview of the first rows in the results table.
Is the data real? No. All values are generated randomly on your device. They may resemble real names or addresses by coincidence, but they are not real personal data.
Can I control the ranges? Yes. Integer, float and date fields accept custom minimum and maximum values, and custom list fields accept your own choices.
Can I create nested objects? Yes — add an object field and give it its own child fields, or add arrays of primitives and arrays of objects.
Do I need to sign up? No. The tool is free, requires no account, and sends nothing to any server.
Does the SQL export work with my database? The generated INSERT statements use standard syntax and correct quoting, and work with MySQL, PostgreSQL, SQLite and similar engines.
SCHEMA produces realistic-looking random data for development and testing. It is not a source of real personal information and must not be used to fabricate real identities or documentation. Never use generated data for production records, authentication or anything where accuracy matters. For high-volume work, remember generation happens in your browser, so very large exports are limited by your device's memory.
For more details on how this site handles your data, see our Privacy Policy.
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