nanoid.cr

Codacy Badge Crystal CI GitHub release Docs License

Crystal implementation of original NanoID

Installation

Add this to your application's shard.yml:

dependencies:
  nanoid:
    github: mamantoha/nanoid.cr

Usage

require "nanoid"

Nanoid.generate uses URL-friendly symbols (A-Za-z0-9_-) and returns an ID with 21 characters.

Nanoid.generate
# => 3gFI8yZxcfXsXGhB0036l

If you want to reduce ID length (and increase collisions probability), you can pass the length as an argument.

Nanoid.generate(size: 8, alphabet: "1234567890abcdef")
# => 86984b57

Non-secure API is also available.

Nanoid.generate(secure: false)
# => no0MmiInNcBm9jR2_3sGt

Nanoid.generate(size: 10, alphabet: "1234567890abcdef", secure: false)
# => 2793b2351c

Benchmark

crystal run --release ./bench/benchmark.cr

Crystal 1.20.2 (2026-05-15)

LLVM: 22.1.6
Default target: aarch64-apple-darwin25.5.0

    Nanoid.simple_generate(21)   4.02  (248.69ms) (± 0.48%)  76.3MB/op   2.40× slower
   Nanoid.complex_generate(21)   3.27  (306.11ms) (± 2.61%)  91.6MB/op   2.96× slower
Nanoid.non_secure_generate(21)   9.65  (103.58ms) (± 1.75%)  45.8MB/op        fastest
                       UUID v4   3.87  (258.20ms) (± 1.28%)   168MB/op   2.49× slower
    Nanoid.simple_generate(36)   4.05  (246.65ms) (± 2.05%)   107MB/op   1.62× slower
   Nanoid.complex_generate(36)   3.06  (326.75ms) (± 0.98%)   122MB/op   2.14× slower
Nanoid.non_secure_generate(36)   6.55  (152.59ms) (± 1.58%)  61.0MB/op        fastest
                       UUID v4   3.82  (261.80ms) (± 1.85%)   168MB/op   1.72× slower

Development

Clone this repository and install dependencies:

shards install

Run tests:

crystal spec

Contributing

  1. Fork it (https://github.com/mamantoha/nanoid.cr/fork)
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request

Contributors

License

Copyright: 2018-2026 Anton Maminov ([email protected])

This library is distributed under the MIT license. Please see the LICENSE file.