GUID Generator
Generate Microsoft-style GUIDs (Globally Unique Identifiers) in your browser. Same as UUID v4 under the hood, but with the conventions Microsoft tooling expects: uppercase, optional curly braces, and the canonical 8-4-4-4-12 hyphen layout. Powered by the Web Crypto API — nothing leaves your machine.
The Microsoft GUID format
A GUID is just a UUID written with Microsoft's preferred decorations: uppercase and optional curly braces. Same 128 random bits.
{F47AC10B-58CC-4372-A567-0E02B2C3D479}
Used in COM, .NET, Windows Registry,
SQL Server uniqueidentifier, etc.f47ac10b-58cc-4372-a567-0e02b2c3d479 Same 128 bits, lowercase, no braces. Used by most non-Microsoft tooling.
What you'll use this for
UUIDs are the universal "give me a unique identifier" tool — no central coordination required.
Windows Registry
Class IDs (CLSIDs), Interface IDs (IIDs), and Application IDs all use the GUID-with-braces format.
SQL Server
The uniqueidentifier type stores GUIDs. NEWID() generates them server-side; this generates them client-side.
.NET attributes
COM interop, assembly identity, Visual Studio project templates — they all want GUIDs.
Test fixtures
Quickly seed deterministic-looking but unique IDs for sample data in any tooling.
How to generate GUIDs
Set how many
Pick a count from 1 to 1,000. The default of 10 covers most use cases.
Pick a case
UPPERCASE is the Microsoft convention. Lowercase if you're integrating with non-MS tools.
Toggle braces & hyphens
Braces wrap each GUID in {…} for COM/.NET. Hyphens are nearly always on.
Copy or download
Copy all GUIDs to clipboard or save as .txt. Nothing leaves your browser.
Frequently asked questions
None technically — they're the same 128-bit identifier. GUID is the term Microsoft uses; UUID is the cross-platform term from RFC 4122. Microsoft GUIDs are usually written uppercase, often wrapped in {…}.
Microsoft's COM and .NET tooling traditionally formats GUIDs as {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}. The braces are just convention — they help when embedding GUIDs in code where you want clear delimiters.
Yes. GUID v4 has 122 random bits — about 5.3 × 10^36 possible values. Collisions are theoretically possible but practically impossible.
The identifier itself is hex, so the case carries no extra meaning. But many tools and registries do exact-string comparison, so stick to the convention your stack expects (typically UPPERCASE in Microsoft worlds).
Yes. No signup, no limits, no ads. Generation happens entirely in your browser via the Web Crypto API.
About GUIDs
A GUID (Globally Unique Identifier) is Microsoft's name for what the rest of the world calls a UUID. Same 128-bit identifier defined in RFC 4122; different stylistic conventions.
Microsoft formats
{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}— registry, COM, CLSIDXXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX— .NETGuid.ToString("D")XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX— .NETGuid.ToString("N")
Where you'll see GUIDs
- Windows Registry — Class IDs (CLSIDs), Interface IDs (IIDs), AppIDs.
- SQL Server — the
uniqueidentifiercolumn type andNEWID(). - .NET / COM — assembly identity, interop attributes, project templates.
- Office docs — embedded as document properties and revision tags.