Developer Essentials · Free Tool

NanoID Generator

Generate compact, URL-safe NanoIDs with a custom size and alphabet — an unbiased, cryptographically-random alternative to UUIDs. See the entropy live. Runs in your browser.

Latest ID

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How it works

NanoID builds an identifier by drawing cryptographically-secure random bytes with getRandomValues and mapping them onto your chosen alphabet using a bitmask — rejecting out-of-range values so every character is uniformly likely (no modulo bias). The default 21-character URL-safe ID has ~126 bits of entropy, comparable to a UUID but shorter and safe in URLs.