Generate CUID

Generate a compact Cuid-style identifier for client or server records.

freeworks offlinenothing uploaded
ToolCUID Generator
Input
Output
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Preview

How it works

A Cuid starts with c and combines a millisecond timestamp, counter, fingerprint, and random block encoded in base36. These fields reduce collisions during rapid calls and across processes.

  • The prefix and base36 alphabet work in HTML and URLs.
  • The counter separates calls made in the same millisecond.

Worked example

Single CUID
Generate one collision-resistant CUID
Input
											1
Output
												cmt8nqxba0000lwkhpod76fhf

When to use this

Offline-first records, comments, and temporary client IDs generate Cuids.

Edge cases

  • The finite counter wraps and relies on fresh randomness.
  • Collision resistance is not a database uniqueness guarantee.
  • Timestamp ordering is approximate rather than globally strict.

References