STEP 1: CHECK YOUR UNSEND SETTINGS
Start by signing into Gmail with your account. Then select the gear icon in the upper-right corner, just above your email list. From this menu, select Settings.
STEP 2: ADJUST SETTINGS IF NECESSARY
The settings menu holds all the special features you can activate or adjust in Gmail. Scroll down the General tab until you see the Undo Send section. Here, you will see an option to adjust the Send cancellation period. You can choose how long you have to be able to recall an email. You can choose for up to five, 10, 20, or 30 seconds after you sent it.
If you are worried about sending the wrong email, you probably want to set the cancellation period to at least 10 seconds, just to be safe. Five seconds isn’t very long to realize you made a mistake and hit the unsend option. When finished, scroll to the bottom of the Settings section and save your changes.
Note that the email may show up in the inboxes of those you sent it to while the unsend option is present. Recalling the email will make it disappear, but it’s possible that someone could have started reading it, so it’s still important to act quickly.
STEP 3: SEND A TEST EMAIL
Now that you know how long you have to recall an email, it’s time to test the service out. Hit Compose and address a quick email to yourself. When you are ready, hit the blue Send button.
Now, immediately look in the lower left corner of your Gmail window. You should see a quick sent notification pop up there that says Message sent and gives you an option to view the message or create a new one. In the middle of the notification bar will be an option to Undo.
If you wait you will see the Undo option vanish. That means that your cancellation period has ended and it is now too late to recall the email. If you aren’t sure how long to set your cancellation period for, we suggest you try this several times just to get a feel for how long different periods last.
Hit the Undo option, and you will see that your email pops back up in the same state it was when you sent it. This allows you to freely change the content or address it before sending it as intended. Once the email has been recalled, there’s no time limit on how long you have to work on it — or you can simply delete it and start over.
Recalling an email on iOS or Android
Recalling an email on iOS or Android isas easy as it is on the web browser and doesn’t require you to tweak any settings or options. After sending an email, you’ll see the option to Undo sending it at the bottom of the screen (though on the right, rather than the left). Hit that button, and you should be good to go. Note that the button will only show up for a few seconds, so be sure to act fast.
As with the web client, we recommend sending a test email to see if this feature works for your account before you start relying on it.