List all developers on a project in Git

To show all users & emails, and the number of commits in the CURRENT branch:

git shortlog --summary --numbered --email

Or simply:

git shortlog -sne

To show users from all branches (not only the ones in the current branch) you have to add --all flag:

git shortlog -sne --all

If you want to be more specific in the list (find a list of unique committer and author), you could use git log:

git log --pretty="%an %ae%n%cn %ce" | sort | uniq

• %an author name
• %ae author email
• %n new line
• %cn committer name
• %ce committer email

Other placeholders are described in the pretty print documentation of git log.

You can try this:

git log | grep Author: | sort | uniq

(users that have done commits)

Note: by default git shortlog groups commits by authors.

If you need to group them by committers, you will need Git 2.12 (Q1 2017)

git shortlog -snc

See commit 03f4082 (16 Dec 2016) by Jeff King (peff).
See commit fbfda15 (11 Oct 2016) by Linus Torvalds (torvalds).
^{(Merged by Junio C Hamano -- gitster -- in commit ad1b4e2, 27 Dec 2016)}

Linus Torvalds himself introduces this feature:

shortlog: group by committer information

In some situations you may want to group the commits not by author, but by committer instead.

For example, when I just wanted to look up what I'm still missing from linux-next in the current merge window, I don't care so much about who wrote a patch, as what git tree it came from, which generally boils down to "who committed it".

So make git shortlog take a "-c" or "--committer" option to switch grouping to that.