A UUID (Universally Unique Identifier) is a 128-bit label used for unique identification in computer systems. UUID v4 is randomly generated, providing approximately 5.3 x 10^36 possible values, making collisions virtually impossible.

How do I generate a UUID online?

Click the Generate button or adjust the quantity to generate multiple UUIDs at once. The tool uses your browser's crypto.randomUUID() API for secure random generation. Copy any UUID by clicking the copy button next to it.

Is this UUID generator secure?

Yes. This tool uses the Web Crypto API (crypto.randomUUID()) which is cryptographically secure. It runs entirely in your browser with no server communication, ensuring your generated identifiers remain private.

Free Developer Tool — 100% Client-Side

UUID Generator Online

Generate random UUID v4 identifiers instantly. Batch generate up to 50 UUIDs with cryptographically secure randomness — no server, no bullshit.

Quantity

Click Generate to create UUIDs.

What Is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit label used for unique identification in computer systems. The term GUID (Globally Unique Identifier) is often used interchangeably, particularly in Microsoft ecosystems. UUID v4 is randomly generated, providing approximately 5.3 × 10³⁶ possible values — making collisions virtually impossible. Our free UUID generator online creates cryptographically secure UUIDs right in your browser.

UUID vs Auto-Increment IDs

UUID

Unique across all systems, databases, and tables
No central coordination needed
Safe in distributed and offline-first architectures
128-bit, takes more storage

Auto-Increment ID

Unique only within a single table
Requires sequential generation
Collisions when merging databases
32/64-bit integer, compact storage

Why UUID v4 Is Used

Distributed Databases — Generate unique keys offline without conflicts when syncing.
API Design — Use UUIDs as resource identifiers that can't be enumerated or guessed.
Microservices — Each service generates its own IDs without a central authority.
Event Sourcing — Unique event IDs that work across event stores and message buses.
Client-Side Generation — Create IDs on the client before server submission (optimistic UI).

Is UUID Safe?

UUID v4 uses random number generation. Our tool uses the Web Crypto API (crypto.randomUUID()), which is cryptographically secure. This means your generated UUIDs are not predictable and are suitable for security-sensitive applications like session tokens, API keys, and resource identifiers.

How to Generate UUIDs

Set the quantity (1–50) and click Generate. Each UUID is displayed in a separate row with its own copy button. Use Copy All to copy every UUID to your clipboard at once — one per line, perfect for batch inserts or API payloads.