How to list installed Homebrew packages

A Homebrew prefix can grow through direct formula installs, cask apps, and dependency packages pulled in by other formulae. Reading the installed inventory before cleanup, migration, or upgrade work shows what Homebrew currently manages instead of what the shell happens to find on PATH.

Formulae and casks use different records. Formulae usually provide command-line tools and libraries, while casks manage app bundles, fonts, plugins, and other artifacts. brew list can show both, but separated views make audits and handoffs easier to read.

Leaves narrow the formula inventory to items that are not dependencies of another installed formula or cask. That view is useful before cleanup because dependency packages can still be required even when they look unfamiliar in the full list.

1. List all installed Homebrew entries.

   $ brew list
   ada-url
   adwaita-icon-theme
   aom
   apr
   apr-util
   argon2
   ##### snipped #####
   zsh-completions
   zstd
   anydesk
   betterdisplay
   ##### snipped #####
   zoom

   brew list combines formulae and casks in one read-only inventory. Use the separated formula and cask lists when the package type matters.

2. List only installed formulae.

   $ brew list --formula
   ada-url
   adwaita-icon-theme
   aom
   apr
   apr-util
   argon2
   ##### snipped #####
   wget
   zsh-completions

   Formulae are Homebrew packages for command-line tools, libraries, and dependencies. Use --formula when a cleanup, upgrade, or audit task should ignore app-style casks.

3. List only installed casks.

   $ brew list --cask
   firefox
   google-chrome
   iterm2
   postman
   ##### snipped #####
   vlc
   zed
   zoom

   Casks are Homebrew-managed apps, fonts, plugins, and similar artifacts. No output means Homebrew has no installed casks in the current prefix.

4. Show installed formula versions.

   $ brew list --versions --formula
   ada-url 3.4.4
   adwaita-icon-theme 50.0
   aom 3.14.1
   apr 1.7.6
   ##### snipped #####
   wget 1.25.0
   zsh-completions 0.36.0

   --versions adds local formula versions to the inventory. For a fuller package record, inspect the package directly with brew info.
   Related: How to check Homebrew package information

5. List formula leaves.

   $ brew leaves
   awscli
   bash
   bash-completion
   dos2unix
   dosbox-x
   ##### snipped #####
   wget
   zsh-completions

   brew leaves lists installed formulae that are not dependencies of another installed formula or cask. Casks are not part of the leaf list.

6. Limit the leaf list to formulae installed on request.

   $ brew leaves --installed-on-request
   awscli
   bash
   bash-completion
   dos2unix
   ##### snipped #####
   wget
   zsh-completions

   --installed-on-request keeps the final list focused on formulae Homebrew records as manually requested. If this output is shorter than brew leaves, the omitted leaf formulae were installed as dependencies.