Delete already merged branches
The code example below shows how to delete all branches which have already been merged into the current branch:
$ git branch
feature-1
feature-2
feature-3
* master
$ git branch --merged
feature-1
* master
$ git branch --merged | egrep -v "(^\*|master)"
feature-1
$ git branch --merged | egrep -v "(^\*|master)" | xargs git branch -d
Deleted branch feature-1 (was 1d7fd54).Check out this great Stack Overflow answer for more information.