This will remove all branches (except for master), even if the branch has a slash “https://stackoverflow.com/” in it:
git branch -r | grep 'origin' | grep -v 'master$' | grep -v HEAD | cut -d/ -f2- | while read line; do git push origin :heads/$line; done;
This will do the same, leaving both develop and master branches alone:
git branch -r | grep 'origin' | grep -v 'master$' | grep -v 'develop$' | grep -v HEAD | cut -d/ -f2- | while read line; do git push origin :heads/$line; done;
This is the script for fish shell:
git branch -r | grep 'origin' | grep -v 'master$' | grep -v 'develop$' | grep -v HEAD | cut -d/ -f2- | while read line; git push origin :heads/$line; end;