How many UUIDs can I generate at once?

Up to 100 UUIDs per generation. For larger volumes, click Generate multiple times and combine the results.

Can a batch contain duplicate UUIDs?

Each UUID comes from its own call to the browser's cryptographic random generator, with 122 random bits per value. A repeat inside a batch of 100 is so unlikely that it can be ignored in practice, though the tool does not check the list for duplicates.

Can I download the UUIDs?

Yes. Click the Download button to save all generated UUIDs as a plain text file, one UUID per line.

Where are the UUIDs generated?

In your browser, with crypto.randomUUID() for each value. Our servers are not involved at any point.

Bulk UUID generator

Need multiple UUIDs at once? Generate up to 100 random UUID v4 values in one click. Each UUID appears on its own line so you can copy them individually or all at once.

0 UUIDs

VERSION

COUNT

Runs entirely in your browser

How it works

Each value in the list comes from its own call to crypto.randomUUID, or to crypto.getRandomValues with the version and variant bits set in browsers without randomUUID. The count field accepts 1 to 100, and the list is joined with line breaks for copying or for the uuids.txt download.

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 many UUIDs can I generate at once?: Up to 100 UUIDs per generation. For larger volumes, click Generate multiple times and combine the results.
Can a batch contain duplicate UUIDs?: Each UUID comes from its own call to the browser's cryptographic random generator, with 122 random bits per value. A repeat inside a batch of 100 is so unlikely that it can be ignored in practice, though the tool does not check the list for duplicates.
Can I download the UUIDs?: Yes. Click the Download button to save all generated UUIDs as a plain text file, one UUID per line.
Where are the UUIDs generated?: In your browser, with crypto.randomUUID() for each value. Our servers are not involved at any point.

Last reviewed September 30, 2026

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