Mac notebooks: About standby mode

Mac notebooks that support standby mode are:

• MacBook Pro (Retina, 13-inch, Late 2012 and later)
• MacBook Pro (Retina, 15-inch, Early 2013 and later)
• MacBook Pro (Retina, Mid 2012)
• MacBook Air (Mid 2010) and later

The standby mode activates after just over an hour of "regular" sleep. To enter standby, the computer must:

• Be running on battery power.
• Have no USB devices attached.
• Have no SD card inserted.
• Have no Bluetooth devices currently paired.
• Have no external display attached.
• Have Power Nap disabled (if it is supported on your Mac).

A computer with a fully charged battery can remain in standby for up to thirty days without being plugged into an AC power source. 

The state of the computer is saved to the flash storage (SSD), then the power to the hardware subsystems turns off to increase the length of the standby. For example, RAM memory and the USB bus are powered off during the standby.

To exit standby, do any one of the following:

• Press a key.
• Open the lid.
• Click the trackpad.

When the computer exits standby, the state of the system image stored on the flash storage is used to restore the system to its pre-standby state. The computer returns to full operation within a few seconds. 

If you leave the computer in standby long enough for the battery to deplete fully, the computer will shut down. You can recover your computer to its pre-standby state and any unsaved work should not be lost. To exit standby at this point, attach the computer to an AC power source and press the Power button.