UUID Generator (v4)
Generate cryptographically random version 4 UUIDs in bulk. Choose uppercase, hyphenless or braced formats and copy instantly.
1–500
About UUID Generator
Generate version 4 UUIDs — 128-bit identifiers with 122 random bits — for database primary keys, correlation IDs and idempotency tokens. Randomness comes from the Web Crypto API, the same cryptographically secure source your browser uses for TLS, not from Math.random.
How to use it
- Choose how many UUIDs to generate.
- Pick a format: standard, uppercase, no hyphens or braced.
- Generate, then copy all or copy one at a time.
Frequently asked questions
Can two v4 UUIDs collide?
In theory yes, in practice no. You would need to generate about 2.7 × 10^18 of them for a one-in-a-billion chance of a single collision.
Are these safe to use as security tokens?
They are generated with crypto.getRandomValues, so the randomness is suitable. But UUIDs are often logged and shared, so prefer a dedicated secret for authentication.
What is the difference between v4 and v7?
v4 is fully random. v7 embeds a timestamp so IDs sort chronologically, which is friendlier to database indexes. This tool generates v4.
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