Keep your Mac awake during downloads

Start with a temporary fix

For a download already running in your browser, open Terminal and enter:

caffeinate -i -t 7200

This asks macOS to prevent idle system sleep for two hours. Keep that Terminal process running and leave the laptop lid open. Press Control+C in Terminal to stop it early. It does not force the display to stay on.

The time is in seconds. Choose a duration that covers the download, rather than leaving your computer awake indefinitely. This command does not resume failed transfers or make a slow connection faster.

Screen off is not the same as asleep

A dark display does not necessarily mean the computer has stopped working. System sleep is the state that matters here. Locking your screen is also different from putting the Mac to sleep.

On supported Mac laptops, Battery settings include an option to prevent automatic sleep on the power adapter while the display is off. Settings vary by model and macOS version; follow Apple’s sleep settings guide for your Mac. Restore your usual settings when you no longer need them.

When AfterLid makes sense

If you do this often and prefer a visible app control, AfterLid gives you named power modes instead of a command to remember. Use Awake for work with the lid open, and return to Sleepy when you are done. Awake keeps the Mac and display awake; it does not automatically turn the display off.

Start with a short download while you are at the desk. Confirm that progress continues with your intended setup before leaving a larger transfer unattended. Get AfterLid and follow the setup steps.

If the download still stops

Check the connection, available disk space, the download server and any browser error. A power tool cannot fix an expired link, a disconnected VPN or an app that quit. Some apps already prevent idle sleep while transferring files, so changing power behavior may not solve the original problem.

For the tradeoffs between the command and the app, read Caffeinate vs AfterLid. If your task is an export rather than a transfer, see the rendering guide.