Merge multiple JPGs into single PDF in Linux

I used the following command to convert and merge all the JPG files in a directory to a single PDF file: convert *.jpg file.pdf The files in the directory are numbered from `1.jpg` to `123.jpg`. The conversion went fine but after converting, the pages were all mixed up. I wanted the PDF to have pages from `1.jpg` to `123.jpg` in the same order as they are named. I tried it with the following command as well: cd 1 FILES=$( find . -type f -name "*jpg" | cut -d/ -f 2) mkdir temp && cd temp for file in $FILES; do BASE=$(echo $file | sed 's/.jpg//g'); convert ../$BASE.jpg $BASE.pdf; done && pdftk *pdf cat output ../1.pdf && cd .. rm -rf temp But still no luck. Operating system is Linux.