Free Online UUID v4 Generator

Generate random Universally Unique Identifiers (UUID / GUID) securely using cryptographic entropy in your browser.

Quantity

Uppercase Include Hyphens

Generated Identifiers

About Free Online UUID v4 Generator

Generate cryptographically secure RFC 4122 Version 4 UUIDs (Universally Unique Identifiers) instantly. Built using the browser's hardware-backed crypto.randomUUID() engine, ASToolHub delivers mathematically random, collision-free identifiers for database primary keys, testing, and distributed systems.

How to Use Free Online UUID v4 Generator Online

Select Quantity

Choose how many UUIDs to generate at once (from 1 to 100 identifiers).

Configure Format Options

Toggle hyphens on or off, and switch between standard lowercase and uppercase output.

Generate Identifiers

Click Generate UUIDs to compute fresh, cryptographically random identifiers.

Copy to Clipboard

Copy individual UUIDs or click Copy All to paste the entire list directly into your database seed file or code.

Key Features & Privacy Benefits

Hardware Cryptographic Entropy: Powered by window.crypto.randomUUID() using your operating system's cryptographic random number generator.
RFC 4122 v4 Standard Compliance: Strictly adheres to Version 4 UUID specifications with correct variant and version bits set.
Bulk Generation up to 100: Produce batches of up to 100 UUIDs instantly for database seeding, automated testing, and mock fixtures.
Custom Output Formatting: Supports standard hyphenated format (8-4-4-4-12) or clean compact strings, in uppercase or lowercase.

Frequently Asked Questions

What is a Version 4 UUID?

A UUID v4 is a 128-bit universally unique identifier generated using random numbers. The probability of generating a duplicate UUID v4 is practically zero (one in billions of billions).

Is crypto.randomUUID() secure for production databases?

Yes. It uses the operating system's CSPRNG (Cryptographically Secure Pseudorandom Number Generator), making it suitable for distributed primary keys, session tokens, and transaction IDs.

What is the difference between UUID and GUID?

GUID (Globally Unique Identifier) is Microsoft's terminology for the UUID standard. Functionally, UUID v4 and GUID v4 are identical.