brew info --json

brew info --json helm@2
brew info --json postgresql

List available versions, note will not show current version and do not work on casks:

brew info --json postgresql | jq -r '.[].versioned_formulae[]' 

brew info --json terraform | jq -r '.[].versioned_formulae[]'

Activities

• Homebrew: list available package versions

See also

• brew: update | upgrade | autoupdate | install | uninstall | services | list, cask | cleanup | doctor | test | link | unlink | changelog | tap | info | search | install --cask | analytics off | --prefix | --version | brew --help ]

https://stackoverflow.com/a/59569730