Google has announced it will formally add an "undo send" feature for Gmail users.

“Undo send” allows people using Gmail to cancel a sent mail if they have second thoughts immediately after sending. Web-based users will be able to retract an email within five to 30 seconds.

The company experimented with the option for six years in the Labs section of Gmail’s settings.

The feature is turned off by default for those not currently using the Labs version and can be enabled from the General tab in Gmail settings.