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Bulk UUID v4 Generator

Used by developers, writers, and creators worldwide.

The bulk UUID v4 generator creates up to 100 RFC 4122-compliant identifiers in a single click — no setup, no server calls. UUID v4s are built entirely from random bits, meaning no timestamps or MAC addresses are embedded, and no coordination between nodes is needed. That makes them safe to generate anywhere. Set the count, choose lowercase or uppercase hex, and optionally wrap each ID in curly braces (for SQL Server and .NET) or square brackets (for custom config schemas). The output lands one UUID per line, ready to paste straight into a SQL script, JSON fixture, or seed file without reformatting.

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How to use

  1. Choose your options above
  2. Click Generate
  3. Copy your result

Detailed instructions

  1. Set the count field to the number of UUIDs you need, between 1 and 100.
  2. Choose Uppercase if your target system or codebase requires capital hex characters.
  3. Select a brace style — curly for SQL Server or .NET GUIDs, square for custom schemas, or none for standard use.
  4. Click Generate to produce the full list of formatted UUIDs instantly.
  5. Copy the output with the Copy All button and paste directly into your SQL script, fixture file, or code.

Use Cases

  • •Seeding a PostgreSQL users table with 50 unique UUID primary keys for local dev
  • •Pre-generating curly-brace GUIDs for a SQL Server migration script or .NET ORM fixture
  • •Populating a JSON test fixture array for a REST API integration suite in Postman
  • •Assigning idempotency keys to a batch of queued background jobs before enqueuing
  • •Building a CSV import file with uppercase UUID row identifiers for a legacy data pipeline

Tips

  • →For SQL INSERT scripts, generate with curly braces off and paste UUIDs directly into a VALUES block wrapped in single quotes.
  • →If you need UUIDs as a JavaScript array, copy the list and wrap it with square brackets, then add quotes — or use the square bracket option to speed up manual formatting.
  • →Regenerate rather than reuse: if you accidentally use the same UUID list twice in test data, foreign key conflicts or duplicate-key errors can be hard to trace.
  • →For SQL Server migrations, enable curly braces and uppercase together to match the GUID format SQL Server Management Studio displays natively.
  • →When pre-seeding lookup or enum tables, generate exactly as many UUIDs as rows needed and number them in a comment — it makes the seed script easier to audit later.
  • →If your ORM expects binary UUID storage, generate lowercase without braces and convert using UUID_TO_BIN() in MySQL or gen_random_uuid() idioms — the format here gives you the cleanest starting point.

FAQ

how is uuid v4 different from v1 or v7

UUID v4 is generated purely from random bits — no timestamp, no hardware address. UUID v1 embeds the current time and MAC address, which can expose system info. UUID v7 adds a millisecond timestamp prefix for sortability, making it better for high-volume database inserts where index fragmentation is a concern.

are uuid v4s safe to use as database primary keys

Yes, and they're the standard choice in PostgreSQL (native uuid type), MySQL (CHAR(36) or binary(16)), MongoDB, and DynamoDB. The one trade-off is that random UUIDs don't insert in order, which can fragment B-tree indexes at very high write volumes. If that matters, UUID v7 or a ULID is worth considering.

why would I wrap uuids in curly braces instead of using plain format

SQL Server stores GUIDs in curly-brace format like {550e8400-e29b-41d4-a716-446655440000}, and many .NET ORMs and COM interfaces expect the same convention. Generating them pre-wrapped here means you can paste directly into T-SQL scripts or C# config files without any post-processing step.