Free GUID Generator
Generate cryptographically random GUIDs (the Microsoft-flavored 128-bit identifier) in bulk. Choose brace wrapping, uppercase hex, and how many you need — perfect for database keys, COM components, config files, and anywhere a globally unique ID is required.
Generated GUIDs
How to Use the GUID Generator
- Set how many GUIDs you need (1–100).
- Toggle braces { } and uppercase to match your platform’s style.
- Click Generate for fresh cryptographically random GUIDs.
- Copy one or copy all to the clipboard.
Features
GUIDs are generated with the Web Crypto API (crypto.getRandomValues), not Math.random, so they are suitable for real uniqueness requirements. Output follows the canonical 8-4-4-4-12 format with version-4 and variant bits set correctly. Bulk mode produces up to 100 at once, each on its own line, with per-line and copy-all actions.
Benefits & Use Cases
Windows and .NET developers grab {braced} GUIDs for assembly attributes and registry keys; database designers seed unique primary keys; testers generate collision-free fixture IDs. Because generation is local and cryptographically strong, the values are safe to use directly in real systems.
Tips
SQL Server’s UNIQUEIDENTIFIER accepts both braced and unbraced forms. When generating IDs for URLs, use lowercase without braces — shorter and cleaner. Never reuse a GUID across environments if it identifies a distinct entity; generate fresh ones here in bulk.
Frequently Asked Questions
What is a GUID?
A GUID (Globally Unique Identifier) is a 128-bit value written as 32 hexadecimal digits in 8-4-4-4-12 groups, e.g. 550e8400-e29b-41d4-a716-446655440000. The space of possible values is so large that random GUIDs are effectively unique.
What is the difference between a GUID and a UUID?
They are the same 128-bit format. “GUID” is Microsoft’s term (often shown with braces), while “UUID” is the open-standard term from RFC 4122. A version-4 GUID from this tool is a valid UUID v4.
Are these GUIDs really random?
Yes. They are generated with the operating system’s cryptographic random number generator via the Web Crypto API, with the version and variant bits set per the spec.
Should GUIDs be uppercase or lowercase?
Both are valid — hex digits are case-insensitive. Microsoft tools traditionally display uppercase with braces; web and Linux tooling usually prefers lowercase without braces.
Can two GUIDs collide?
Theoretically yes, practically never: with 122 random bits, you would need to generate billions per second for centuries before a collision became likely.
Is generation private?
Completely. GUIDs are created locally in your browser; nothing is sent to or stored on any server.
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