CUID Generator
Generate collision-resistant, lowercase IDs for distributed systems.
Generate CUID-style identifiers — short, lowercase alphanumeric strings designed to avoid collisions across distributed servers and clients. Use them as primary keys, public IDs, or anywhere you need an opaque, copy-friendly token.
Common use cases
- Primary keys for Prisma, MongoDB and SQL tables
- Public IDs in URLs (e.g. /products/cl9hu2kxd000)
- Client-side IDs that won't clash with server-side ones
- Token IDs for distributed event streams
Frequently asked questions
What is CUID?▾
CUID is a family of collision-resistant ID formats popular with the Prisma ORM and Node.js community. They're shorter than UUIDs and start with a letter.
Are these v1 or v2?▾
We generate CUID2-style IDs: lowercase letter prefix plus base36 timestamp + random tail. They're URL-safe and case-insensitive.
Are they really collision-free?▾
Practically yes for any single application. With 24-character defaults you'd need to generate billions per second across the planet to hit a collision.