idgen

A CLI tool for generating random identifiers with customizable alphabets and block formatting.

Install

Homebrew

brew install nikbucher/tap/idgen

Pre-built binaries

Download the latest binary for your platform from GitHub Releases:

Platform	Architecture	Download
Linux	x86_64	idgen-x86_64-unknown-linux-gnu.tar.gz
Linux	aarch64	idgen-aarch64-unknown-linux-gnu.tar.gz
macOS	Intel	idgen-x86_64-apple-darwin.tar.gz
macOS	Apple Silicon	idgen-aarch64-apple-darwin.tar.gz
Windows	x86_64	idgen-x86_64-pc-windows-msvc.zip
Windows	aarch64	idgen-aarch64-pc-windows-msvc.zip

Extract the archive and place the idgen binary somewhere on your PATH.

Cargo

cargo install idgen

From source

git clone https://github.com/nikbucher/idgen.git
cd idgen
cargo install --path .

Usage

# Generate a single ID with defaults (lowercase, 20 chars, blocks of 4)
idgen

# Generate 5 IDs
idgen -n 5

# Use uppercase ambiguity-safe alphabet
idgen -a uppercase

# Custom size, block size, and delimiter
idgen -s 16 -b 4 -d .

# Quiet mode (no config output, just the ID)
idgen -q

# Combine options
idgen -a all -s 32 -b 8 -d _ -n 3 -q

Synopsis

$ idgen --help
Generate random identifiers

Usage: idgen [OPTIONS]

Options:
  -a, --alphabet <ALPHABET>
          Alphabet to use for ID generation

          Possible values:
          - nanoid:                  NanoID / URL-safe Base64: _-0-9a-zA-Z
          - all:                     All alphanumeric: 0-9a-zA-Z
          - uppercase:               Ambiguity-safe uppercase: excludes B, D, I, O, S, Z
          - all-uppercase:           All uppercase: 0-9A-Z
          - lowercase:               Ambiguity-safe lowercase: excludes 1, l
          - all-lowercase:           All lowercase: 0-9a-z
          - uppercase-and-lowercase: Ambiguity-safe mixed case: excludes B, D, I, K, O, S, Z, k, l

          [default: lowercase]

  -b, --block-size <BLOCK_SIZE>
          Number of characters per block

          [default: 4]

  -d, --delimiter <DELIMITER>
          Delimiter between blocks

          [default: -]

  -s, --size <SIZE>
          Total number of characters in the generated ID

          [default: 20]

  -n, --count <COUNT>
          Number of IDs to generate

          [default: 1]

  -q, --quiet
          Suppress config output

      --completions <SHELL>
          Generate shell completion script and exit

          [possible values: bash, elvish, fish, powershell, zsh]

  -h, --help
          Print help (see a summary with '-h')

  -V, --version
          Print version

Alphabets

Alphabets marked as ambiguity-safe exclude characters that look alike when read on screen or in print — such as 0/O, 1/l, 8/B — making generated IDs easier to read, type, and communicate verbally.

Name	Characters	Description
nanoid	_-0-9a-zA-Z	NanoID / URL-safe Base64 (64 chars)
all	0-9a-zA-Z	All alphanumeric (62 chars)
uppercase	34679ACEFGHJKLMNPQRTUVWXY	Ambiguity-safe uppercase (excludes 0, 1, 2, 5, 8, B, D, I, O, S, Z)
all-uppercase	0-9A-Z	All uppercase (36 chars)
lowercase	023456789abcdefghijkmnopqrstuvwxyz	Ambiguity-safe lowercase (excludes 1, l)
all-lowercase	0-9a-z	All lowercase (36 chars)
uppercase-and-lowercase	34679ACEFGHJLMNPQRTUVWXY...	Ambiguity-safe mixed (excludes 0, 1, 2, 5, 8, B, D, I, K, O, S, Z, k, l)

Shell Completions

Tab completion is supported for bash, zsh, fish, powershell, and elvish.

Homebrew

Completions for bash, zsh, and fish are installed automatically.

Manual

Generate and install the completion script for your shell:

# bash (Linux)
idgen --completions bash | sudo tee /etc/bash_completion.d/idgen

# bash (macOS with Homebrew-installed bash)
idgen --completions bash > "$(brew --prefix)/etc/bash_completion.d/idgen"

# zsh — place in any directory on your $fpath
idgen --completions zsh > "${fpath[1]}/_idgen"

# fish
idgen --completions fish > ~/.config/fish/completions/idgen.fish

# PowerShell — add to $PROFILE
idgen --completions powershell | Out-String | Invoke-Expression

Releasing

Releases are automated via GitHub Actions. To create a new release:

git tag -a v0.1.0 -m "Initial release"
git push origin v0.1.0

This triggers a cross-platform build and creates a GitHub Release with binaries for Linux, macOS, and Windows. The Homebrew formula is updated automatically.

Documentation

• Vision — project goals and scope
• Use cases — functional specifications

License

MIT