UUID Generator
Generates UUIDs in bulk (v4 by default) for test data or unique identifiers.
Generate UUIDs online for free — v4 random, v1 time-based, v3/v5 namespace UUIDs and NIL, with one-click copy.
Steps and notes
What is UUID Generator — v4, v1, v3, v5 and NIL IDs?
A UUID (Universally Unique Identifier) is a 128-bit label, and version 4 — the default here — is generated from random data. With about 122 random bits, the chance of two v4 UUIDs colliding is negligible, so machines can generate identifiers independently without any central coordinator. This tool can also produce v1, v3 and v5 when you need time- or name-based identifiers.
- Choose how many you need
- Click generate
- Copy and use them
- UUID v4 is random and not time-sortable; use ULID if you need an ordered identifier
Frequently asked questions
- Can two generated UUIDs ever collide?
- Theoretically yes, practically no — you would need to generate billions per second for a long time to reach even a coin-flip chance. Databases keep unique constraints as a backstop, not because you will hit it.
- UUID v4 or ULID — which one do I need?
- v4 is completely random, so sorting by UUID says nothing about creation order. If identifiers land in database indexes where insertion order matters, a time-ordered format such as ULID or UUID v7 performs better.
- Are the generated UUIDs sent anywhere?
- No. They are generated locally in your browser and never leave the page.
Category: Crypto
ID generators workflow
UUID Generator — v4, v1, v3, v5 and NIL IDs → ULID Generator — Time-Ordered, Sortable IDs Online → Nano ID Generator — Short, URL-safe Unique IDs Online → Token Generator → Password Generator → OTP code generator → BIP39 passphrase generator