git branch -r | grep <remote> | cut -c 10- | xargs -n 10 git push <remote> --delete
Useful for clean forked repository.
10 in cut -c 10-
here represents the length of string <remote>\
10 in xargs -n 10
represents how many branch to delete at a time, sometimes detele will report error, so less branches a time can reduces number of branched to be deleted manually