What is Sqids?

Sqids (pronounced "squids") is an open-source library that lets you generate YouTube-looking IDs from numbers. These IDs are short, can be generated from a custom alphabet and are guaranteed to be collision-free. Read more .

This is what they look like:



Haskell code is located at https://github.com/sqids/sqids-haskell

To encode & decode:

case sqids (encode [1, 2, 3]) of
  Left  {} -> print "Something went wrong."
  Right id -> print id -- "86Rf07"

case sqids (decode "86Rf07") of
  Left  {}      -> print "Something went wrong."
  Right numbers -> print numbers -- [1, 2, 3]

Randomize IDs by providing a custom alphabet:

case runSqids defaultSqidsOptions{ alphabet = "FxnXM1kBN6cuhsAvjW3Co7l2RePyY8DwaU04Tzt9fHQrqSVKdpimLGIJOgb5ZE" } (encode [1, 2, 3]) of
  Left  {} -> print "Something went wrong."
  Right id -> print id -- "B4aajs"

Enforce a minimum length for IDs:

case runSqids defaultSqidsOptions{ minLength = 10 } (encode [1, 2, 3]) of
  Left  {} -> print "Something went wrong."
  Right id -> print id -- "86Rf07xd4z"

Read more at https://github.com/sqids/sqids-haskell

If you're looking for the original Hashids Haskell, you can find it here .

Why use them?

The main use of Sqids is purely visual. If you'd like to use IDs instead of numbers in your webapp, Sqids could be a good choice:

Use Cases

  • Link shortening Safe to use in URLs
  • Event IDs Collision-free encoding/decoding
  • One-Time Passwords Short & profanity-free

Not Good For

  • Sensitive data This is not an encryption library
  • User IDs Can be decoded, revealing user count


  • 🆔 Generate short IDs from non-negative numbers
  • Easy encoding & decoding
  • 🫣 Auto-generated IDs do not contain common profanity
  • 🎲 Support for custom IDs through shuffled alphabet
  • 😍 40 programming languages (20 using new design)
  • 📌 Every version produces the same IDs
  • 🍻 Small library with a permissive license

Example / Playground