diff --git a/Library/Homebrew/dev-cmd/contributions.rb b/Library/Homebrew/dev-cmd/contributions.rb
index 3bdc2832bb..ed4a8d2138 100755
--- a/Library/Homebrew/dev-cmd/contributions.rb
+++ b/Library/Homebrew/dev-cmd/contributions.rb
@@ -171,9 +171,16 @@ module Homebrew
 
       puts "Determining contributions for #{person} on #{repo_full_name}..." if args.verbose?
 
+      commits_authored = GitHub.repo_commit_count_for_user(repo_full_name, person, "author", args)
+      commits_committed = GitHub.repo_commit_count_for_user(repo_full_name, person, "committer", args)
+      # Only count committers where the author is not the same person. Avoid negative numbers or subtracting zero.
+      if commits_authored.positive? && commits_committed.positive?
+        commits_committed = commits_authored - commits_committed
+      end
+
       data[repo] = {
-        author:        GitHub.repo_commit_count_for_user(repo_full_name, person, "author", args),
-        committer:     GitHub.repo_commit_count_for_user(repo_full_name, person, "committer", args),
+        author:        commits_authored,
+        committer:     commits_committed,
         coauthorships: git_log_trailers_cmd(T.must(repo_path), person, "Co-authored-by", args),
         reviews:       GitHub.count_issues(
           "",