# picom-trans > Set the window opacity for the `picom` window compositor. > More information: . - Set the currently focused window opacity to a specific percentage: `picom-trans --current --opacity {{90}}` - Set the opacity of a window with a specific name: `picom-trans --name {{Firefox}} --opacity {{90}}` - Set the opacity of a specific window selected via mouse cursor: `picom-trans --select --opacity {{90}}` - Toggle the opacity of a specific window: `picom-trans --name {{Firefox}} --toggle`