How to Modify Git Commit Messages

Git provides two ways to modify commit messages, depending on the scenario. Here's a complete guide:

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一、Most Common: Modify the Last Commit Message

Use case: Just committed, noticed a typo in the message, haven't pushed to remote yet.

Command

git commit --amend

Steps

1. Run the command, and Git will open your default editor
2. Modify the first line (the commit message)
3. Save and exit
   • Vim: Press i to edit → make changes → press Esc → type :wq and Enter

One-liner (skip editor)

git commit --amend -m "New commit message"

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二、Advanced: Modify Historical Commit Messages

Use case: Need to modify a commit that's not the most recent one.

Steps

1. View commit history to find the parent commit hash of the target commit:

   git log

2. Run interactive rebase (replace commit-id with the parent hash):

   git rebase -i commit-id

3. In the editor, change pick to reword for the commits you want to modify
4. Save and exit, Git will prompt you to edit each marked commit's message
5. Rebase completes automatically when done

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⚠️ Important Warnings (Must Read)

1. If commit has already been pushed to remote

• You must force push to overwrite:

  git push --force-with-lease

• NEVER force push on public/team branches - it will overwrite others' work!

2. Best Practices

• Only modify history on your private branch that hasn't been pulled by others
• Use --force-with-lease instead of --force for safer force pushes

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Bonus: Modify Commit Author

Change author info without editing the message:

git commit --amend --author="Shing Rui <[email protected]>" --no-edit

For historical commits, use interactive rebase with edit instead of reword, then:

git commit --amend --author="New Author <[email protected]>" --no-edit
git rebase --continue

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Summary

Scenario	Command
Modify last commit	git commit --amend
Modify historical commits	git rebase -i <parent-commit-id>
Force push after modification	git push --force-with-lease (private branches only)
Change commit author	git commit --amend --author="Name <email>"

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Remember: Rewriting Git history is powerful but dangerous. Always be cautious when modifying commits that have been shared with others.