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GUID Generator

Used by developers, writers, and creators worldwide.

A GUID generator gives you instant access to one or more Globally Unique Identifiers — Microsoft's 128-bit UUID implementation used to uniquely identify objects across systems without central coordination. The format you pick has real consequences: braced GUIDs for .NET's Guid.Parse(), hyphenless strings for compact NoSQL document IDs, uppercase for legacy COM interfaces. Set the count, choose lowercase, uppercase, braced, or no-hyphens, and copy the whole batch directly into your migration script, test fixture, or config file. GUIDs are built on UUID v4, so uniqueness comes from randomness rather than timestamps or hardware addresses. The collision probability — roughly 1 in 5.3 undecillion — means you can generate them client-side and use them across distributed systems without any central registry.

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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 GUIDs you need, from 1 up to your desired batch size.
  2. Choose a format from the dropdown: lowercase, uppercase, braced for .NET, or no-hyphens for compact storage.
  3. Click Generate to produce the full list of GUIDs instantly.
  4. Click Copy or select all output text, then paste directly into your code, SQL script, or test fixture.

Use Cases

  • •Seeding primary key columns in a SQL Server or PostgreSQL migration script with braced or lowercase GUIDs
  • •Populating GUID fields in .NET Entity Framework model scaffolding using Guid.Parse()-compatible braced format
  • •Generating no-hyphen correlation IDs for distributed service request tracing in a microservices log pipeline
  • •Creating unique asset IDs for Unity GameObjects or Unreal Engine actors in bulk for a level-design fixture
  • •Producing placeholder client IDs for OAuth app registrations or Postman environment variable sets

Tips

  • →Use braced format when pasting into Visual Studio project files — the IDE expects the curly-brace wrapper by default.
  • →Generate 20–30 at once when writing unit tests; having extras on hand avoids re-running the tool mid-session.
  • →For PostgreSQL UUID columns, lowercase hyphenated format matches the output of gen_random_uuid() and avoids conversion overhead.
  • →Paste no-hyphens GUIDs into Elasticsearch or DynamoDB document IDs where hyphens in the key string can confuse query parsers.
  • →If you need GUIDs that sort chronologically, this tool's random output won't help — use a UUIDv7 generator or NEWSEQUENTIALID() in SQL Server instead.
  • →When storing GUIDs in MySQL, use BINARY(16) and strip the hyphens — the varchar approach wastes 20 bytes per row at scale.

FAQ

what is the difference between a GUID and a UUID

They are the same thing. UUID is the open RFC 4122 standard; GUID is Microsoft's name for the identical 128-bit identifier. You'll see GUID in Windows, COM, and .NET documentation and UUID everywhere else — they share the same format, structure, and collision probability, and are fully interchangeable.

are random GUIDs safe to use as database primary keys

Yes, with one caveat: random GUIDs as clustered primary keys in SQL Server cause index fragmentation because rows insert randomly rather than at the end. Use NEWSEQUENTIALID() in SQL Server or UUIDv7 if you need append-friendly ordering. For non-clustered indexes or PostgreSQL, random GUIDs work cleanly.

when should I use the no-hyphens GUID format instead of the standard one

Stripping hyphens produces a compact 32-character hex string, useful for URL slugs, certain NoSQL document IDs, and file names where hyphens conflict with tooling. Always document that the field is a stripped GUID so future developers know it's not an arbitrary hex hash.