Generate CUID2

Generate a lowercase, URL-safe Cuid2-style identifier for a public record.

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ToolCUID2 Generator
Input
Output
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How it works

A lowercase letter prefix is followed by a collision-resistant digest derived from time, counter, entropy, and session context; optional length truncates the identifier. The result is opaque public-ID text.

  • The prefix keeps IDs valid as common names.
  • Entropy and a counter reduce collisions during rapid calls.

Worked example

Default CUID2
Generate a 24-character CUID2
Input
											Length: 24
Count: 1
Output
												hwbcdbcysksymsffqpayvczh

When to use this

Web URLs, optimistic client records, and opaque database keys use Cuid2-style IDs.

Edge cases

  • Shortening the ID reduces collision resistance.
  • An ID is not a cryptographic secret.
  • Clock changes do not make IDs strictly monotonic.

References