Developer Tools
~/uuid-generator
// Generate UUID v4 instantly in your browser. Bulk, copy all, no signup.
UUID v4
Randomly generated universally unique identifier - 128-bit value with ~5.3 x 10^36 possible values.
Bulk Generate
Generate up to 100 UUIDs at once. Copy all with one click for batch use.
Browser-only
Uses native crypto.randomUUID() - cryptographically secure, no server calls.
// FAQ
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify information in computer systems. Format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
Is UUID v4 truly unique?
UUID v4 is randomly generated. The probability of a duplicate is astronomically low - around 1 in 5.3 x 10^36. Safe to use as unique IDs in any system.
Is this cryptographically secure?
Yes. This tool uses the browser native crypto.randomUUID() which is backed by a cryptographically secure random number generator.
What is the difference between UUID v4 and other versions?
UUID v1 is time-based and includes the machine MAC address. UUID v3 and v5 are name-based hashes. UUID v4 is fully random, which makes it the safest choice when you do not want to leak any system information.
Can I use these UUIDs in a database primary key?
Yes. UUID v4 is widely used as a primary key in PostgreSQL, MySQL, and other databases. Just be aware that random UUIDs can cause index fragmentation in large tables - consider ULIDs or UUID v7 for insert-heavy workloads.
Are the generated UUIDs stored anywhere?
No. UUIDs are generated and displayed entirely in your browser. Nothing is sent to or saved on our servers.
// Common Use Cases
Database primary keys
Use UUID v4 as a primary key to ensure uniqueness across distributed systems or when merging data from multiple sources.
File and asset naming
Rename uploaded files with a UUID to prevent collisions and avoid exposing sequential IDs in storage paths.
Test data and seeds
Generate bulk UUIDs quickly when seeding a test database or populating fixture files for automated tests.
Correlation IDs
Attach a UUID to each request in a distributed system to trace it across services in logs and monitoring tools.