How do I choose how many UUIDs to generate?

Type a whole number from 1 to 100 in the count field in the side panel. The list regenerates with that many values as you type.

What format is the downloaded file?

A plain text file named uuids.txt with one lowercase UUID per line, separated by line feeds, and no header row.

Can I paste the list into a spreadsheet?

Yes. Each UUID sits on its own line, so pasting the copied list into a spreadsheet column puts one UUID in each cell.

Is the data sent to a server?

All generation runs in your browser using crypto.randomUUID(). Our servers are not involved at any point.

Generate a list of UUIDs

Generate a list of up to 100 random UUID v4 values for seeding databases, creating test fixtures, or pre-allocating IDs. Each UUID sits on its own line, ready to paste into a seed script or save as a text file. All generation runs in your browser.

0 UUIDs

VERSION

COUNT

Runs entirely in your browser

How it works

The count field in the side panel takes a whole number from 1 to 100, and the list regenerates as you type. Each value comes from its own call to crypto.randomUUID, and the values are joined with line breaks, so Copy puts the whole list on your clipboard and Download saves it as uuids.txt with one UUID per line.

Processing runs in your browser

UUIDs are generated entirely in your browser. All processing happens locally in your browser tab. Our servers are not involved at any point. You can inspect this yourself in your browser's DevTools Network tab.

Technical specification

UUID version 4 (random) is defined in RFC 9562 (IETF, 2024), which replaced RFC 4122. A UUID v4 contains 122 random bits; the remaining 6 bits encode the version (4) and variant (10xx in bits 64–65). This tool uses the browser's crypto.randomUUID() method (W3C Web Cryptography API), which provides cryptographically strong randomness from the operating system's CSPRNG, equivalent to /dev/urandom on Linux or BCryptGenRandom on Windows.

Standard: RFC 9562: Universally Unique IDentifiers (UUIDs)
Random bits: 122 bits (of 128 total; 6 bits encode version/variant)
Format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
Collision probability: ~50% at 2.7 × 10¹⁸ UUIDs generated

Related operations

For hashing identifiers into fixed-width values, try the hash generator. To produce strong random secrets, use the password generator. For encoding identifiers for transport, see Base64.

Frequently asked questions

How do I choose how many UUIDs to generate?: Type a whole number from 1 to 100 in the count field in the side panel. The list regenerates with that many values as you type.
What format is the downloaded file?: A plain text file named uuids.txt with one lowercase UUID per line, separated by line feeds, and no header row.
Can I paste the list into a spreadsheet?: Yes. Each UUID sits on its own line, so pasting the copied list into a spreadsheet column puts one UUID in each cell.
Is the data sent to a server?: All generation runs in your browser using crypto.randomUUID(). Our servers are not involved at any point.

Last reviewed September 30, 2026

Other pages for this tool

Related tools

Background reading: Complete guide to data tools