How to undo the last commit in Git

"Undo the commit, KEEP my changes" (most common)

git reset --soft HEAD~1
# commit gone, all changes back in staging, ready to
# re-commit. nothing is lost. this is the safe default.

"Undo the commit AND throw away the changes"

git reset --hard HEAD~1
# ⚠ commit gone AND your edits gone. make sure you mean it.
# (deleted the wrong thing? see reflog at the bottom — recoverable)

"The commit is fine, the MESSAGE is wrong"

git commit --amend -m "the message I meant to write"

# forgot to include a file? add it, then amend without editing:
git add forgotten.py
git commit --amend --no-edit

"I already PUSHED it" — the safe public undo

git revert HEAD
# creates a NEW commit that cancels the last one.
# history moves forward; teammates are unaffected. push it.

git revert abc1234        # same, for any older commit by hash

"Undo the last N commits"

git reset --soft HEAD~3    # last 3 commits → back into staging as one pile
# then re-commit as one clean commit — DIY squash

"I reset --hard and I need it BACK"

git reflog
# shows every position HEAD has been, including "deleted" commits:
#   a1b2c3d HEAD@{0}: reset: moving to HEAD~1
#   f4e5d6c HEAD@{1}: commit: the one you want back  ←

git reset --hard HEAD@{1}  # back to before the disaster
# git keeps orphaned commits ~30 days. panic is optional.