GUID / UUID Generator
Generate unique identifiers in various formats — perfect for database keys, API tokens, and more.
Options
Generated GUIDs
// Click Generate to create GUIDsCryptographically Random
Uses the Web Crypto API which leverages OS-level entropy for true randomness.
Batch Generate
Generate up to 50 GUIDs at once. Perfect for seeding database test data.
Copy All
One-click copy of all generated GUIDs to your clipboard, ready to paste.
What is a GUID?
A GUID (Globally Unique Identifier), also called a UUID (Universally Unique Identifier), is a 128-bit number used to uniquely identify information in computer systems. The standard representation uses 32 hexadecimal digits split into five groups by hyphens: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
GUIDs are widely used in .NET as database primary keys (Guid.NewGuid()), session identifiers, correlation IDs for distributed tracing, and anywhere a unique identifier is needed without central coordination.
GUID Format Reference
| Format | Specifier | Example |
|---|---|---|
| Default (with hyphens) | D | 6b29fc40-ca47-1067-b31d-00dd010662da |
| No hyphens | N | 6b29fc40ca471067b31d00dd010662da |
| Curly braces | B | {6b29fc40-ca47-1067-b31d-00dd010662da} |
| Parentheses | P | (6b29fc40-ca47-1067-b31d-00dd010662da) |
| Uppercase | — | 6B29FC40-CA47-1067-B31D-00DD010662DA |
Frequently Asked Questions
What is the difference between a GUID and a UUID?
GUID is Microsoft's term, UUID is the IETF standard. They are functionally identical — both are 128-bit identifiers.
How do I generate a GUID in C#?
Use Guid.NewGuid() to generate a version 4 (random) GUID with a cryptographically secure random number generator.
Are these GUIDs cryptographically secure?
Yes. This tool uses the browser's crypto.getRandomValues() API — the same quality used by operating systems for security.
Can I use GUIDs as database primary keys?
Yes, and it's a common .NET pattern. GUIDs allow generating IDs client-side without a database roundtrip.
What is UUID v4?
UUID version 4 is randomly generated — all bits (except for the version and variant bits) are random. It's the most commonly used UUID type for general purposes.