Just my code snippet I am using to batch convert jpg all images in one folder on the commandline. It uses imagemagick’s mogrify to resize all pictures to max 1500px with 80% jpg compression and strips all EXIF Tags.
Basically what you want in 99% of times on the web.
find ./ -name "*.jpg" -exec mogrify -resize "1500x1500>" -strip -quality 85 {} \;