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nano

NanoID Generator

Generate NanoIDs with length and alphabet presets.

Generate NanoIDs with crypto.getRandomValues. Choose length, alphabet, and count — plus a collision-probability estimate.

ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_- (64 chars)

21
1–64
Entropy
126 bit
Alphabet size
64
~P(collision) / 1M
<1e-15

About NanoID Generator

NanoID produces compact, URL-friendly unique string IDs—by default 21 characters from a 64-char alphabet (A–Z a–z 0–9 _ -). They are shorter and more readable than UUIDs, handy for client keys and public slugs. toco.tools bulk-generates NanoIDs with configurable length (1–64), alphabet presets or a custom charset, and count (up to 500). Randomness comes only from crypto.getRandomValues with bitmask rejection sampling to avoid modulo bias. Entropy (bits) and an approximate collision probability for 1M IDs are shown. Everything runs locally in your browser.

How to use

  1. Pick alphabet and length
  2. Set count and regenerate
  3. Copy the results

FAQ

How does NanoID differ from UUID?

NanoID is a short string ID with configurable length and alphabet. UUIDs are fixed 128-bit values with a longer default string form.

Why is the default length 21?

It matches the official nanoid default—about 126 bits of entropy with the 64-character URL-safe alphabet.

Are NanoIDs sent to a server?

No. Generation runs entirely in your browser.