Free Online UUID Generator
Generate one or up to 50 random UUID v4 identifiers in a single click. Copy them individually or all at once — perfect for seeding test data, creating database keys, or any time you need a guaranteed-unique identifier.
Number of UUIDs to generate: 5
What is a UUID?
A UUID (Universally Unique Identifier), also known as a GUID (Globally Unique Identifier), is a 128-bit identifier formatted as 32 hexadecimal digits in five groups separated by hyphens: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
Version 4 UUIDs (UUID v4) are generated using random or pseudo-random numbers. The probability of a collision is astronomically low — roughly 1 in 5.3 × 10³⁶ — making them safe to use as unique keys without any central coordination.
How to Use the UUID Generator
- Set the count using the slider — from 1 to 50 UUIDs at a time.
- Click Generate UUIDs to create a fresh batch.
- Copy individually by clicking the Copy button next to each UUID, or use Copy All to copy the entire list.
Common Use Cases
- Database primary keys: Use UUIDs instead of auto-increment integers to avoid collisions when merging data from multiple sources.
- Test data generation: Quickly produce a batch of unique IDs to seed development databases or unit tests.
- Session identifiers: Generate unpredictable session tokens for authentication flows.
- File naming: Rename uploaded files with UUIDs to prevent collisions in storage buckets.
Frequently Asked Questions
Astronomically unlikely — roughly 1 in 5.3 × 10³⁶ for any two UUID v4 values. You would need to generate billions of UUIDs per second for billions of years before a collision became statistically probable, which is why UUIDs are considered safe to use as unique keys without any central coordination.
UUID v4 (what this tool generates) is based entirely on random numbers. Other versions encode different information: v1 includes a timestamp and network identifier, v5 is derived deterministically from a namespace and name via hashing. v4 is the most common choice when you just need a unique, unpredictable identifier with no extra structure.
Yes. Generation uses the Web Crypto API's crypto.getRandomValues(), a cryptographically secure random number source — the same class of randomness used for security-sensitive values like session tokens.
Yes, use the slider to generate anywhere from 1 to 50 UUIDs in a single click, then copy them individually or all at once with Copy All.
It's completely free with no limits and no account required. Since generation happens locally in your browser, there's nothing to sign up for.