About ULID & NanoID Generator

ULID & NanoID Generator makes two kinds of identifier. A ULID packs a millisecond timestamp and 80 random bits into 26 Crockford base32 characters, so ULIDs sort by creation time. A NanoID is a short random URL-safe string.

The random bytes come from the browser's secure source. Nothing is sent anywhere.

How to use it

  1. Generate a batch of ULIDs or NanoIDs.
  2. Set the count, and for NanoID the size and alphabet.
  3. Paste a ULID into the decoder to read its timestamp.

Common questions

Why choose a ULID over a UUID?

ULIDs are sortable by time and slightly shorter in text. UUID v4 is more widely supported. UUID v7 is a newer sortable option.

Can two ULIDs collide?

In the same millisecond the chance is set by the 80 random bits, which is vanishingly small for normal volumes.

Is the ULID timestamp reliable?

It is the time the ULID was generated, to the millisecond, and anyone can read it. Do not put a ULID where the creation time should be secret.

Does anything leave my browser?

No. The tool runs entirely on this page.