UUID Generator
This UUID generator creates random v4 identifiers instantly. Generate one or bulk-create up to 100 UUIDs with one-click copy.
About UUID Generator
UUIDs (Universally Unique Identifiers) are the backbone of modern distributed systems. Our UUID Generator creates cryptographically random version 4 UUIDs right in your browser, with support for bulk generation of up to 100 identifiers at once.
What is a UUID v4?
A version 4 UUID is a 128-bit identifier generated almost entirely from random data. It follows the format xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx, where "4" indicates the version and "y" is constrained to a specific range (8, 9, a, or b) to indicate the variant. This tool uses the Web Crypto API to ensure high-quality randomness.
Common use cases
Developers use UUIDs as primary keys in databases like PostgreSQL, MongoDB, and DynamoDB because they can be generated on any node without coordination. They also serve as correlation IDs in microservice architectures, idempotency keys for payment APIs, unique file names in cloud storage buckets, and session identifiers in authentication flows.
Bulk generation
Need a batch of IDs for seed data, test fixtures, or a migration script? Set the count to any number between 1 and 100 and generate them all at once. Copy individual UUIDs with a single click or grab the entire list to paste into your code, spreadsheet, or configuration file.
If you need secure random strings instead, the password generator creates customizable random passwords. For hashing data, check out the hash generator. This UUID Generator uses your OS's cryptographic primitives and runs entirely in your browser.
Frequently Asked Questions
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit label used to identify information in computer systems without requiring a central authority. Version 4 UUIDs are generated from random numbers and look like "550e8400-e29b-41d4-a716-446655440000."
Are UUID v4 values truly unique?
While not mathematically guaranteed, the probability of generating a duplicate UUID v4 is astronomically low. You would need to generate about 2.7 quintillion UUIDs before having a 50% chance of a single collision, making them effectively unique for all practical purposes.
When should I use UUIDs?
UUIDs are commonly used as database primary keys, API request identifiers, session tokens, file names, distributed system message IDs, and anywhere you need a unique label without coordinating with a central server.
Is UUID v4 the same as a GUID?
Practically, yes. GUID (Globally Unique Identifier) is Microsoft's term for the same concept. The format and generation method are identical, though Microsoft tools sometimes display them with curly braces.
Can I use UUIDs as URL slugs?
You can, but UUIDs are long and not human-readable, which makes URLs harder to share and remember. They work well as internal identifiers in databases and APIs. For user-facing URLs, a shorter slug or sequential ID is usually a better choice.