UUID Generator
Generate UUID v4 identifiers using the Web Crypto API for true randomness. Create single or bulk UUIDs (up to 100 at once), with options for uppercase and no-hyphens formats. Copy individual UUIDs or all at once. Perfect for database primary keys, session tokens, and unique identifiers in any application.
About UUID v4 Generator
- UUID v4 — Generated using cryptographically secure random values
- Bulk generation — Generate up to 100 UUIDs at once
- Format options — Uppercase and no-hyphens variants
- All processing happens locally in your browser using crypto.getRandomValues()
How to Use
- 1
Set Options
Choose the number of UUIDs to generate (1-100), and toggle uppercase or no-hyphens format if needed.
- 2
Generate
Click Generate to create your UUIDs using cryptographically secure random values.
- 3
Copy Results
Copy individual UUIDs or use Copy All to get all generated UUIDs at once, one per line.
Examples by Niche
f47ac10b-58cc-4372-a567-0e02b2c3d479 — Standard lowercase UUID v4 with hyphens
F47AC10B58CC4372A5670E02B2C3D479 — Uppercase, no hyphens for compact token format
Generate 50 UUIDs at once for seeding a test database or pre-allocating identifiers
Frequently Asked Questions
What is a UUID v4?
UUID v4 (Universally Unique Identifier version 4) is a 128-bit identifier generated using random or pseudo-random numbers. It follows the format xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where x is a random hex digit and y is one of 8, 9, A, or B.
Are these UUIDs truly random?
Yes, this generator uses crypto.getRandomValues() which provides cryptographically secure random values, making the UUIDs suitable for security-sensitive applications.
What is the probability of a UUID collision?
The probability is astronomically low. You would need to generate about 2.71 quintillion (2.71 x 10^18) UUIDs to have a 50% chance of a single collision.
When should I use UUIDs instead of auto-incrementing IDs?
UUIDs are ideal for distributed systems where multiple servers generate IDs independently, when you need IDs before inserting into a database, or when exposing IDs in URLs where sequential numbers would reveal business metrics. Auto-incrementing IDs are simpler and more storage-efficient for single-database applications.
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