Nano ID

Warnings

• breaking Version 2.0.0 changed the default alphabet, replacing '~' with '-'. The default ID length was also reduced from 22 to 21 characters.
  Fix: If migrating from a pre-2.0.0 version, explicitly define the old alphabet and length if consistent ID generation is critical for existing data. Otherwise, IDs generated by v2.0.0 will be different by default.
• gotcha The `non_secure_generate` function uses `random.random` internally and is not cryptographically strong. It is explicitly not recommended for security-sensitive applications like generating tokens or secrets.
  Fix: Always use `generate()` for sensitive applications, which employs cryptographically strong random APIs. Only use `non_secure_generate()` when performance is critical and security is not a concern.
• gotcha Reducing the ID length (e.g., `generate(size=10)`) increases the probability of collisions.
  Fix: Always use an ID collision probability calculator (often linked in Nano ID documentation for various languages) to determine a safe ID length based on your expected number of IDs and desired collision probability.
• gotcha When using custom alphabets, be cautious with characters like `-,.()` at the end of a link in URLs, as they might be misinterpreted as punctuation by some systems.
  Fix: Prefer the default URL-friendly alphabet or ensure that custom alphabets avoid problematic characters for URL contexts. If problematic characters are necessary, ensure proper URL encoding.
• gotcha NanoIDs are non-sequential. Using them as clustered primary keys in a database can lead to significant performance overhead during inserts, as the database may need to reorder records physically on disk to maintain the clustered index order.
  Fix: Avoid using NanoIDs (or UUIDs) as clustered primary keys if insert performance is critical. Consider using them as regular unique identifiers and a separate sequential primary key for clustering, or evaluate the impact on your specific database system.

Install

• pip install nanoid Install stable version

Imports

• generate

  from nanoid import generate

• non_secure_generate

  from nanoid import non_secure_generate

  Use this for non-security-critical applications where performance is prioritized, as it uses pseudo-random generation.

Quickstart

Quickly generate secure, URL-friendly unique IDs. You can specify the length and a custom alphabet. A faster, non-secure generator is also available for less sensitive use cases.

from nanoid import generate, non_secure_generate

# Generate a default 21-character, URL-friendly ID
id_default = generate()
print(f"Default ID: {id_default}")

# Generate an ID with a specified length
id_short = generate(size=10)
print(f"Short ID (10 chars): {id_short}")

# Generate an ID with a custom alphabet and length
id_custom = generate('1234567890abcdef', 16)
print(f"Custom Alphabet ID: {id_custom}")

# Generate a non-secure ID (faster, but not for sensitive use)
id_non_secure = non_secure_generate()
print(f"Non-Secure ID: {id_non_secure}")