UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify information in distributed systems. The most common format is a 36-character string, for example: 550e8400-e29b-41d4-a716-446655440000.

What is the difference between UUID v4 and v7?

UUID v4 uses random number generation and is the most commonly used version. UUID v7 embeds a timestamp, making it sortable by time, ideal for database indexing. v4 is suitable for scenarios requiring pure randomness, v7 for scenarios requiring time ordering.

What is the difference between UUID and GUID?

UUID and GUID are essentially the same concept. GUID is Microsoft’s implementation of UUID, both formats are identical. In Windows development it is commonly called GUID, on other platforms it is usually called UUID.

Is the online UUID generator safe?

Our UUID generator runs entirely in your browser locally, using crypto.randomUUID() and crypto.getRandomValues() to generate cryptographically secure random numbers. Your UUIDs are never sent to any server, ensuring complete privacy and security.

UUID Generator - Free Online UUID/GUID Generator Tool

What is a UUID?

UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify information in distributed systems. UUID is also known as GUID (Globally Unique Identifier) - both are essentially the same concept.

The standard UUID format is a 36-character string consisting of 32 hexadecimal digits and 4 hyphens:

550e8400-e29b-41d4-a716-446655440000

time_low - time_mid - time_hi+version - clock+variant - node

UUID Version Comparison

Version	Generation Method	Characteristics	Use Cases
UUID v4	Random numbers	Completely random, unordered	Session IDs, temporary identifiers
UUID v7	Timestamp + random	Time-sortable, traceable	Database primary keys, distributed IDs

UUID vs GUID: What's the Difference?

UUID and GUID are essentially the same concept, just with different naming origins:

UUID: Standard name defined by IETF in RFC 4122
GUID: Microsoft’s implementation name, widely used in Windows development

Both formats are identical and interchangeable. If you're a Windows developer, you can use our tool to generate GUIDs.

Why Choose an Online UUID Generator?

🔒 Completely Secure

All generation happens locally in your browser, UUIDs are never sent to any server

⚡ Lightning Fast

No network latency, batch generate up to 1000 UUIDs instantly

🛠️ Multiple Formats

Support JSON array, no hyphens, case conversion output formats

✅ UUID Validator

Built-in UUID validator to parse version, variant, and timestamp

Can UUIDs Be Duplicated?

Theoretically UUIDs can be duplicated, but the probability is extremely low:

UUID v4 duplication probability is approximately 1 in 2¹²²
Even generating 1 billion UUIDs per second for 85 years, you might only get one duplicate
In practical applications, UUID duplication probability is negligible

UUID Generator

UUID Validator

Session Statistics

Complete UUID Guide: From Basics to Practice