UUID Generator
Generate cryptographically secure RFC 4122 Version 4 UUIDs and GUIDs in batches up to 100.
Privacy First: 100% Client-Side Processing
Processed in your browser. Files are never uploaded.
How to Use the UUID Generator – Version 4 RFC 4122 GUIDs
- 1Select the number of UUIDs you want to generate (from 1 to 100).
- 2Choose formatting options: Uppercase vs lowercase, or toggle hyphens.
- 3Click 'Re-generate' to create a fresh batch using cryptographic randomness.
- 4Click 'Copy Result' or 'Export' to download the UUID list as a text file.
Formula & How It Works
RFC 4122 Version 4 Cryptographic Standard
A Version 4 UUID contains 128 bits: 122 random bits, 4 bits indicating Version 4 ('0100'), and 2 bits indicating the RFC 4122 variant ('10'). Generation uses window.crypto.randomUUID() for high-entropy randomness.
Worked Examples
Standard RFC 4122 v4 UUID
Input: Standard lowercase with hyphens
Explanation: Notice the '4' at the 13th character position, identifying Version 4.
Uppercase Database GUID
Input: Uppercase toggle enabled
Explanation: Formats hex digits in uppercase for Microsoft SQL Server uniqueidentifier compatibility.
Clean Hash without Hyphens
Input: Without hyphens toggle
Explanation: 32-character hexadecimal string without separating hyphens.
Batch Generation
Input: Quantity: 5 UUIDs
Explanation: Generates multiple independent identifiers simultaneously.
Frequently Asked Questions
What is a UUID / GUID?▼
A UUID (Universally Unique Identifier) or GUID (Globally Unique Identifier) is a 128-bit identifier standardized to be globally unique without central coordination.
What are the odds of two UUID v4 values colliding?▼
The probability of a collision is approximately 1 in 2¹²² (roughly 1 in 5.3 × 10³⁶), making accidental duplicates mathematically negligible.
Is this generator cryptographically secure?▼
Yes, it uses crypto.randomUUID() backed by your browser's CSPRNG (cryptographically secure pseudo-random number generator).
What is the difference between UUID and GUID?▼
GUID is Microsoft's terminology for UUID. They represent the identical 128-bit RFC 4122 standard.
Can I generate up to 100 UUIDs at once?▼
Yes, you can batch generate up to 100 UUIDs and export them as a .txt file.
Does this tool send generated UUIDs to any database or server?▼
No, all UUID generation occurs 100% within your local browser memory.
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