I've been working on wrap-up articles for my days at phptek 2025 and as part of those posts I've been including some of the pictures I took. As a "lazy programmer," I'm always looking to automate even the smallest thing like creating 25 thumbnails so instead of spending 5 minutes just making the thumbnails I instead spent 30 finding the exact command line tool and its set of options to do it repeatedly.

For my and your future reference, it's this:

convert input.JPG -resize 400 input-400.JPG