Bulk UUID v4 Generator Online (Instant)

About Our Free UUID v4 Generator Tool

A Universally Unique Identifier (UUID), also known as a Globally Unique Identifier (GUID), is a 128-bit label standardized under RFC 4122. Version 4 UUIDs rely on random numbers to produce identifiers with such extreme statistical uniqueness that the odds of generating a duplicate are practically zero. They are standard in distributed databases, microservice event queues, and REST API primary keys.

UtilDash's UUID v4 Generator creates individual or bulk UUIDs (up to 500 at a time) using the browser's cryptographically secure window.crypto.getRandomValues() API. This ensures strong cryptographic randomness compared to basic tools that rely on predictable pseudorandom functions.

Customize your UUIDs to fit your target environment: toggle standard hyphens on or off, switch between uppercase and lowercase letters, and export your list as plain text, a JSON array, or an SQL insert statement with a single click.

UUIDs in Modern Distributed Databases: In modern cloud architectures using distributed databases like Cassandra, CockroachDB, and PostgreSQL, sequential auto-incrementing integer IDs create primary key generation bottlenecks and security risks (as competitors can guess total user counts). UUID v4 provides decentralized, collision-proof primary keys that microservices can generate independently without database roundtrips.

Key Features

Cryptographically Strong — Generated via the browser’s Web Crypto API
Bulk Generation — Generate from 1 to 500 unique UUIDs simultaneously
Flexible Formatting — Toggle hyphens, adjust casing, or add quotes
Multi-Format Exports — Copy as plain text, JSON arrays, or SQL insert values
100% Client-Side — Instant generation with zero server overhead

How to Use UUID v4 Generator

Select how many UUIDs you want to generate (e.g. 1, 10, 50, or 100).
Choose your formatting options (hyphens, uppercase/lowercase).
Click "Generate UUIDs" to produce your unique identifiers.
Copy the output as plain text or export as a JSON array.

Frequently Asked Questions

What are the chances of two UUID v4 values colliding?

The probability is so close to zero as to be practically impossible. You would need to generate approximately 1 billion UUIDs per second for 85 years to have a 50% probability of a single collision.

What is the structure of a UUID v4?

A standard UUID consists of 32 hexadecimal digits displayed in 5 groups separated by hyphens (8-4-4-4-12), with the version digit set to 4 (e.g. xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx).

Are these UUIDs safe for database primary keys?

Yes. UUID v4 identifiers are safe for distributed database primary keys because they can be generated independently across multiple servers without synchronization conflicts.

What is the difference between UUID v1 and UUID v4?

UUID v1 incorporates the system MAC address and timestamp, which can reveal hardware identity. UUID v4 is generated entirely from cryptographically random numbers, offering superior privacy.