qlmanage

Quick Look Server debug and management tool.

Syntax
      qlmanage -p [-d debugLevel] [-x] [-c contentTypeUTI [-g generator]] [file ...]

      qlmanage -m [name ...]

      qlmanage -r

      qlmanage -t [-d debugLevel] [-x] [-i] [-s size] [-f factor] [-c contentTypeUTI [-g generator]] [file ...]

      qlmanage -h

Key
   
   -p   Display the Quick Look generated previews for the specified file(s).
        This will open the image in a separate window.

   -m   Get all sorts of information on Quick Look server including the list of detected generators.

   -r   Reset the Quick Look Server and all Quick Look client’s generator cache.

   -t   Display the Quick Look generated thumbnails (if available) for the specified files.
        This will open the image in a separate window.

   -h   Help.

qlmanage allows you to test your Quick Look generators and manage Quick Look Server.

Examples

Preview an image:

$ qlmanage -p catmeme.png

Convert an svg to a png:

$ qlmanage -t -s 1024x1024 -o MyIcon.iconset/Icon1024.png icon.svg

“Sometimes not seeing things can be a blessing” ~ August Strindberg

Related macOS commands

Local man page: qlmanage - Command line help page on your local machine.
Reset QuickLook generators and disk cache to resolve issues with IconServicesAgent