IDMint - free, no upload, runs in your browser

Generate UUIDs in bulk, right in your browser

IDMint generates RFC 4122 version 4 UUIDs using the browser's secure crypto, in batches up to 1,000 at a time, with uppercase, hyphen, and brace formatting options. Because the randomness comes from your own machine, no server ever sees the identifiers you mint.

Why UUIDs, and why v4

Universally unique identifiers let different systems mint IDs without coordinating a central counter - a client can create an ID that will never collide with one created on a server. Version 4 UUIDs use random bits, which is the right default for database keys, API resource IDs, and event correlation IDs.

When the IDs are tied to security - reset tokens, invite codes, or anything a user must not guess - the randomness must be cryptographically secure. IDMint uses the browser's Web Crypto API, not Math.random.

The formatting options that stop merge conflicts

Teams collide over formatting more than over the UUIDs themselves: one service stores uppercase without hyphens, another expects lowercase with braces for a Postgres text column. IDMint produces all of them from the same source value, so a table and a test fixture stay consistent.

Downloading the batch as a .txt makes it easy to paste straight into seed scripts, SQL INSERTs, or fixture files.

How to generate a batch of UUIDs

Frequently asked questions

Are these really unique?

Version 4 UUIDs use 122 random bits. The collision risk is so small that generating a billion per second for a century would still make one astronomically unlikely.

Is the randomness cryptographically secure?

Yes. IDMint uses the browser's Web Crypto API (crypto.getRandomValues), the same source behind TLS and session generation. No Math.random anywhere.

Can I generate UUID v1, v3, or v5?

Currently v4 only, which is the right default for almost every application. Timestamp-based v1 adds a privacy leak (the generation time), which is why v4 is preferred.

How many can I generate at once?

Up to 1,000 per run, with no daily quota. Generate again as often as you like.

Do the UUIDs get sent to a server?

No. Randomness comes from your browser and the results never leave your machine.

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