GUID generator
Same 128 bits, Microsoft accent: braces and capitals preset, for registry keys, COM classes, C# scaffolding and anywhere else Windows spells UUID as GUID.
Guide
How to use it
- Generate, braces and uppercase are already on, matching registry and COM conventions.
- Turn braces off for C# Guid.Parse strings and SQL uniqueidentifier literals, both accept plain hyphenated form.
- Bulk-generate for test fixtures with Copy all, one per line.
Examples
Where GUIDs turn up
Windows registry class keys live under braced uppercase GUIDs, the formatting this page presets. Hand-editing the registry is its own adventure, at least the identifier will be well-formed.
In code you would call the framework, this page is for the times you need one outside it: a config file, a test fixture, an interface ID in documentation.
SQL Server’s GUID column type accepts hyphenated form with or without braces. NEWID() generates server-side, paste these for seed data.
Method
How it works
GUID and UUID name the same RFC 4122 structure, GUID being Microsoft’s historical term from COM days. These are v4 (random) via crypto.randomUUID, presented in the braced uppercase style Windows tooling displays.
Comparison is case-insensitive and brace-agnostic everywhere sane: {ABC…} and abc… are the same identifier, dressing differs by ecosystem, bits do not.
FAQ
Frequently asked questions
Is a GUID different from a UUID?
No, same format, same bits, different heritage. Microsoft documentation says GUID, everyone else says UUID, both parse each other happily.
Why the braces?
COM and registry convention from the 1990s: braces made GUIDs visually parseable in config text. Tools raised on that convention still expect them.
Does case matter?
Not to comparison, hex is hex. Some style checkers care cosmetically: registry displays upper, .NET ToString() emits lower, both options are one toggle here.
What version do these use?
v4, random. Old COM GUIDs were v1 (MAC plus timestamp), which leaked machine identity, random replaced it everywhere for good reason.
Can I make a deterministic GUID from a name?
That is v5 (namespace hashing), useful for stable IDs from strings, it needs a namespace and belongs in code, not a random generator.
Same privacy as the UUID page?
Identical: generated locally, seen by nobody, logged nowhere.
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