A UUID (Universally Unique Identifier) is a 128-bit identifier formatted as 32 hex digits in groups: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. Version 4 UUIDs are randomly generated.

How unique is a UUID v4?

The probability of generating two identical UUIDs is astronomically small — roughly 1 in 5.3 × 10³⁶. You can safely treat them as unique.

What is the difference between UUID and GUID?

GUID (Globally Unique Identifier) is Microsoft's term for UUID. They are effectively the same thing.

UUID Generator

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Free online UUID v4 generator. Generate one or multiple random UUIDs (Universally Unique Identifiers) with a single click. Choose uppercase or lowercase, with or without hyphens. Uses the browser's secure random number generator.

Count (max 20)

Hyphens

Uppercase

95f07c82-d6e5-4abd-8bcf-8e5a6f934c9c

fd3289b2-aa0d-4927-a5b3-450a31cd08b7

360f038a-2f5f-4475-aec0-252ea5a49b54

25c38395-7db7-4025-ac2e-5ff56a3c5856

cbbadbe0-cdae-42b1-a475-18d27497d175

Frequently Asked Questions

References

RFC 9562 — Universally Unique IDentifiers (UUIDs) — IETF
crypto.randomUUID() — MDN Web Docs

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Frequently Asked Questions

References and sources

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