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Frequently Asked Questions
 
 What is a UUID? 
A UUID (Universally Unique Identifier) is a 128-bit label used for identifying information in computer systems. UUIDs are standardized by RFC 9562 and are designed to be unique without requiring a central authority.
 
 
 What is the difference between UUID v4 and v7? 
UUID v4 is generated using random or pseudo-random numbers, making it completely unpredictable. UUID v7 embeds a Unix timestamp in the first 48 bits, making it time-sortable while still containing random data — ideal for database primary keys.
 
 
 Are UUID v4 collisions possible? 
Theoretically yes, but practically no. With 122 random bits, you would need to generate about 2.71 quintillion UUIDs to have a 50% probability of a collision. That is astronomically unlikely in any real-world scenario.
 
 
 When should I use UUID v7 instead of v4? 
Use UUID v7 when you need time-sortable identifiers — for example, as database primary keys. Because v7 UUIDs are ordered by creation time, they provide much better index performance in B-tree databases compared to random v4 UUIDs.
 
 
 Is my data safe? 
Yes. All UUIDs are generated entirely in your browser using the Web Crypto API. No data is ever sent to any server. You can verify this in the Network tab of your browser's developer tools.