How to undo git add?

If you have added files to a staging area by running git add command and now want to undo git add operation, then all you have to do is run git reset command.

Lat's say you have added sales.csv file.

$git add sales.csv
$git status
On branch master
Changes to be committed:
  (use "git reset HEAD ..." to unstage)

        modified:   sales.csv

You can see that sales.csv file is in a staging area.

To undo git add operation, run the below command:

$git reset HEAD sales.csv

After running git reset command, you will find that file is in the modified state.

$git status
On branch master
Changes not staged for commit:
  (use "git add ..." to update what will be committed)
  (use "git checkout -- ..." to discard changes in working directory)

        modified:   sales.csv

no changes added to commit (use "git add" and/or "git commit -a")

Here, you can see that sales.csv file is in a modified state.

If you want to undo the changes made to a file, then run git checkout command.

$git checkout -- sales.csv

The below images explains the entire process of undoing git add operation.