daytics™
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How to Use This Tool
A UUID (Universally Unique Identifier) is a 128-bit number commonly written as 32 hexadecimal characters in five groups, separated by hyphens. Version 4 UUIDs are generated from random data — 122 bits of randomness plus 6 fixed bits that identify them as "v4". This tool uses the browser's built-in crypto.randomUUID (or, as a fallback, crypto.getRandomValues), which is cryptographically secure and suitable for production use.
How to Use
- Enter how many UUIDs you want (1–100).
- Pick a Format — lowercase, uppercase, wrapped in braces, or with hyphens removed.
- Click Generate to produce the list.
- Click Copy All to copy the whole block to your clipboard.
Frequently Asked Questions
What is a UUID?
A Universally Unique Identifier — a 128-bit label used to tag items (rows in databases, files, events) so each has a globally unique name without coordination between systems.
UUID v4 vs v1?
v1 embeds a timestamp and MAC address — guaranteed unique, but leaks information. v4 is purely random — almost-certainly unique, reveals nothing about when or where it was made, and is the safe default for most apps.
Is this secure enough for production?
Yes. The tool uses the browser's cryptographic random source (crypto.getRandomValues), which is seeded from operating-system entropy and suitable for security-sensitive use cases.
Can UUIDs collide?
In theory yes, but the probability is astronomically small — with 2^122 possible random UUIDs, you would need to generate roughly 10^18 UUIDs before you saw a 50% chance of any collision. Not a concern for ordinary applications.