UUID Generator: A UUID generator creates universally unique identifiers (UUID v4) that are practically guaranteed to never collide. Generate one or many UUIDs, choose upper or lower case and hyphen style, and copy them instantly — all in your browser.
Frequently Asked Questions
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit value written as 32 hexadecimal characters in five hyphen-separated groups, such as 550e8400-e29b-41d4-a716-446655440000. It uniquely identifies records without a central authority.
What is a version 4 UUID?
A version 4 UUID is generated from random numbers. With 122 random bits, the chance of two v4 UUIDs colliding is so small it's effectively zero, which is why it's the most common type.
How are UUIDs used?
UUIDs are used as primary keys in databases, unique IDs for API requests, session tokens, and file names — anywhere you need a unique identifier that can be created independently across systems.
Are the UUIDs generated here random and secure?
Yes. This tool uses the browser's crypto.randomUUID / getRandomValues, producing cryptographically strong version 4 UUIDs entirely on your device.
What is a UUID?
A UUID is a 128-bit identifier written as 36 characters (32 hex digits plus 4 hyphens) that can be generated independently on any machine with a negligible chance of collision.
SnoopTool generates version 4 UUIDs from the browser's cryptographic random source and can produce them in bulk. A v4 UUID has 122 random bits; you would need to generate about 2.7 × 10¹⁸ of them before a 50% chance of any collision.
UUID Generator: key facts
Reference facts for the SnoopTool UUID Generator, a free browser-based tool.
| Format | 8-4-4-4-12 hex characters, e.g. 3f2504e0-4f89-41d3-9a0c-0305e82c3301 |
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| Version 4 | Randomly generated; 122 random bits |
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| Collision odds | ~50% only after ~2.7 × 10¹⁸ UUIDs |
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| Randomness source | crypto.getRandomValues(), not Math.random() |
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| Other versions | v1 time-based, v5 name-based (SHA-1), v7 time-ordered |
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Why use the SnoopTool UUID Generator?
- Create primary keys that can be generated offline and merged without conflict.
- Produce correlation IDs for tracing a request across services.
- Generate bulk test fixtures in one click.
- Get an ID that reveals nothing about a record's creation time or order.
How to use the UUID Generator (step by step)
- Choose how many. Set the number of UUIDs to generate — one or a bulk batch.
- Generate. Press Generate; the v4 UUIDs appear instantly.
- Copy. Copy a single UUID or the whole list.
- Regenerate. Press again for a fresh, unrelated set.
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