How to undo send in gmail

Did you ever knew that you can undo a sent e-mail in Gmail? It is a lesser known feature, but Google made it even better than it was before. When it was first introduced, you were given just five seconds window during which you could hit “undo.”

Now that’s up to 30 seconds.

This feature is hidden from most of the users who don’t know where it exists. Be aware that the feature is part of Gmail Labs, though. That means it’s still in testing mode and it might not always work as intended.










Procedure:
1)login to your gmail account.
2)In your google mail page click on the green conical flask button

3)On the lab page enable undo send feature.And click on save.

4)By default, Gmail gives you a 10-second window of time in which you may undo a sent e-mail. You can change that to five, 20 or 30 seconds by going to Settings (in the top right corner of the main Gmail page, right next to the Labs icon) and finding the Undo Send section inside the “General” tab.
5)That's it you are done now.
6)Now compose a message and click on send.

7)Click on "undo" button to do undo send.