UUID Generator

Generate universally unique identifiers (UUIDs) instantly. Supports Version 1 and Version 4.

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About UUIDs (Universally Unique Identifiers)

A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information in computer systems. Standardized by the Open Software Foundation (OSF) and RFC 4122, UUIDs allow distributed systems to generate unique IDs without a central coordination authority.

The probability of a collision (two identical UUIDs being generated) is vanishingly small. To put it in perspective, if you generated 1 billion UUIDs every second for the next 100 years, the probability of creating a single duplicate would be about 50%.

Version 4 (Random)

Generated using random or pseudo-random numbers. This is the industry standard for database primary keys, session IDs, and API tokens because it doesn't reveal any information about the generating system.

Version 1 (Time-based)

Generated using the current timestamp and the computer's MAC address (node ID). Uniqueness is guaranteed across space and time, but it can leak the creation time and the generator's identity.

Frequently Asked Questions

Are these UUIDs truly unique?

Yes. While "truly" unique is theoretically impossible with finite numbers, the 128-bit space of a UUID ($3.4 \times 10^{38}$) is so vast that for all practical human purposes, they are unique. You are more likely to be hit by a meteorite than to generate a colliding UUID v4.

Is this tool secure?

Yes, absolutely. This tool runs 100% on your device (Client-Side). The UUIDs are generated using your browser's cryptographic libraries. No data is ever sent to our servers, ensuring your generated IDs remain private.

Can I use UUIDs as Database Primary Keys?

Yes, and it is a common best practice for distributed systems. Unlike auto-incrementing integers, UUIDs allow you to generate IDs offline or on multiple servers without fear of conflict. They also prevent "ID enumeration attacks" where malicious users guess resource URLs (e.g., /user/101 vs /user/102).

Which version should I choose?

For 99% of use cases, choose Version 4 (Random). It is secure, opaque, and has excellent distribution. Use Version 1 only if you specifically need sortability by creation time or need to guarantee uniqueness based on machine identity.

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