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UUID & Nano ID Generator

Generate UUID v4, UUID v7, and Nano IDs in bulk — instantly in your browser.

100% in your browser. Nothing is uploaded.

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Frequently asked questions

What is the difference between UUID v4 and UUID v7?

UUID v4 is entirely random — 122 random bits with no inherent ordering. UUID v7 embeds a 48-bit millisecond timestamp in the first 6 bytes, making the IDs lexicographically sortable by creation time. This matters for database primary keys: v7 inserts at the end of a B-tree index (good for performance) while v4 inserts randomly (causing index fragmentation).

What is Nano ID and when should I use it?

Nano ID produces URL-safe random IDs using a 64-character alphabet. A 21-character Nano ID has roughly the same collision probability as a UUID v4 but is shorter and has no dashes. Use it when you want compact, URL-friendly IDs and do not need the timestamp-sortable property of UUID v7.

Are the IDs generated securely?

Yes. All IDs use crypto.getRandomValues, the Web Crypto API, which is cryptographically secure. Nothing is sent to a server — generation happens entirely in your browser.

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