How do I undo all changes made by a macro?

Explanation

When a macro makes multiple changes, a single u undoes the entire macro as one unit. Each macro execution is treated as one undo step.

How it works

• Run a macro with @a that makes 10 changes
• A single u undoes all 10 changes at once
• Vim groups all changes within a macro into one undo block

Example

A macro that changes three words on a line: after running @a, pressing u reverts all three word changes.

Tips

• This makes macros safe to experiment with
• U is different — it undoes all changes on the current line
• If a macro with a count (50@a) makes wrong changes, u undoes one iteration
• 5u undoes 5 iterations of the macro
• Always test macros on a small sample before running with large counts