UUID Generator

A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information in computer systems. UUIDs follow the RFC 4122 standard and consist of 32 hexadecimal digits displayed in five groups separated by hyphens (8-4-4-4-12). They are designed to be unique across all systems and all times without requiring a central registration authority, making them ideal for distributed systems, database primary keys, transaction IDs, and resource identification.

UUID v4 is the most commonly used version that generates identifiers using cryptographically strong random or pseudo-random numbers. This tool uses the browser's native crypto.randomUUID() function, which leverages the Web Crypto API for maximum security and randomness. UUID v4 is preferred because it requires no network access, no coordination between systems, and has an astronomically low collision probability, making it perfect for modern distributed applications.

UUID v1 is timestamp-based and includes the MAC address of the generating computer, which can reveal information about when and where it was created. UUID v4 is purely random and provides better privacy. UUID v5 is namespace-based and uses SHA-1 hashing to generate deterministic UUIDs from a namespace and name combination. For most applications, UUID v4 (which this tool generates) is recommended due to its simplicity, privacy, and collision resistance.

The probability of a UUID v4 collision is approximately 1 in 5.3 x 10^36 (or 1 in 2^122). This is so astronomically low that it's considered practically zero. To put it in perspective, you would need to generate about 1 billion UUIDs every second for approximately 85 years to have a 50% probability of creating just one duplicate.

Absolutely! All UUID generation happens entirely in your browser using the Web Crypto API. No data, requests, or generated UUIDs are ever transmitted to our servers or any external service. This tool is 100% client-side and works even without an internet connection (once the page is loaded).

You can generate UUIDs in batches of 1, 5, 10, or 25 at a time, and you can click the "Generate" button as many times as you need. There are no rate limits, quotas, or fees. Whether you need a single UUID for testing or hundreds for populating a database, our tool can handle it instantly.

UUIDs are versatile and can be used in: database primary keys (PostgreSQL, MySQL, MongoDB), REST API resource identifiers, distributed system synchronization, transaction tracking, session IDs, file naming conventions, cache keys, message queue identifiers, event tracking systems, microservices communication, and anywhere you need guaranteed uniqueness.

RFC 4122 is the official standard specification for UUIDs. Compliance means that the generated UUIDs follow the exact format, structure, and generation algorithms defined in this standard, ensuring interoperability across different systems, programming languages, and platforms.

Yes! UUIDs are excellent for database primary keys, especially in distributed systems. Benefits include: no need for a central ID generator, natural replication across multiple databases, ability to generate IDs client-side before insertion, and prevention of ID guessing attacks. Modern databases like PostgreSQL have native UUID types optimized for storage and indexing.

This tool works on all modern browsers that support the Web Crypto API and the crypto.randomUUID() method: Chrome 92+, Edge 92+, Firefox 95+, Safari 15.4+, Opera 78+, and their mobile versions.