Generate UUID v4 (random) and UUID v7 (timestamp-sortable) identifiers
122 bits of cryptographic randomness. Ideal for most use cases where temporal ordering doesn't matter. Industry standard, supported everywhere.
550e8400-e29b-41d4-a716-446655440000
Encodes a 48-bit Unix millisecond timestamp in the most-significant bits, making v7 UUIDs naturally sortable by creation time. Better for database primary keys (reduces index fragmentation).
018f8e3d-4b2a-7c1d-9f3e-1a2b3c4d5e6f
↑ First 12 chars encode the timestamp — UUIDs generated later will always sort higher.
crypto.getRandomValues()Generate universally unique identifiers (UUIDs) for database records, distributed systems, and unique resource identification. Our UUID Generator creates version 4 (random) UUIDs using cryptographically secure random numbers—all generated locally for privacy.
A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information in computer systems. Unlike sequential IDs, UUIDs can be generated independently without coordination between systems, making them ideal for distributed systems, database records, and unique resource identification. Our UUID Generator creates cryptographically secure UUIDs with complete local processing for maximum privacy and security.
Unlike many online UUID generators that rely on server-side generation, our tool generates all UUIDs locally in your browser using the Web Cryptography API. This means your UUID generation patterns and the identifiers themselves never leave your computer, providing enterprise-grade security for sensitive applications and data systems.
crypto.getRandomValues() for true random number generation, not pseudo-random algorithms, ensuring maximum uniqueness and security.UUIDs are essential in many distributed computing and data management scenarios:
Follow these best practices for effective UUID implementation:
Our UUID Generator follows industry standards and specifications:
All UUID generation happens entirely within your web browser using the Web Cryptography API. Your UUID generation patterns and the identifiers themselves are never transmitted to our servers or any external service. This local processing ensures:
UUID v4 uses completely random 122 bits, while UUID v7 encodes a 48-bit Unix timestamp (milliseconds) in the most significant bits, making v7 UUIDs naturally sortable by creation time. v7 is better for database primary keys as it reduces index fragmentation.
Extremely unique. The probability of generating a duplicate UUID v4 is approximately 1 in 2^122 (5.3×10^36). To put this in perspective, you would need to generate 1 billion UUIDs per second for about 85 years to have a 50% chance of a single collision.
UUIDs are excellent for distributed databases but have trade-offs: they take more storage (128-bit vs 32/64-bit) and can cause index fragmentation with v4. UUID v7 reduces fragmentation by being time-ordered. Consider your specific database requirements.
Properly generated UUID v4 (using cryptographically secure random numbers) cannot be predicted. UUID v7 contains a timestamp, so the time portion is predictable, but the random portion still provides sufficient unpredictability for most applications.
UUIDs are slightly larger (16 bytes vs 4-8 bytes for integers) which affects storage and memory. Database index performance can be impacted with v4 due to randomness, but v7 improves this by being time-ordered. Network transmission impact is minimal.
Yes, UUIDs in their standard hexadecimal representation (with or without hyphens) are URL-safe as they contain only characters 0-9, a-f, and hyphens. No URL encoding is required when using UUIDs in URLs.