Start with the simple checks. Change one thing at a time so you can tell which step helped.
A demanding app, high screen brightness, background syncing or battery age can change runtime. First, note what changed recently and whether the same issue affects another device. This helps separate a device-specific fault from a wider network or service issue.
Troubleshooting steps
Check the basics
Check Battery settings for apps using notable energy and close only what you do not need. After each change, repeat the action that originally failed and give the device a moment to reconnect or refresh.
Review the settings
Lower brightness and disconnect accessories that are not in use. After each change, repeat the action that originally failed and give the device a moment to reconnect or refresh.
Test one change
Install macOS updates and restart if the drain began after a temporary app problem. After each change, repeat the action that originally failed and give the device a moment to reconnect or refresh.
Confirm the result
Review battery health information and note whether runtime has changed gradually or suddenly. After each change, repeat the action that originally failed and give the device a moment to reconnect or refresh.
Helpful note
If the device becomes unusually hot or the battery appears swollen, stop using it and seek service.
When to get more help
If these checks do not resolve the issue, contact the relevant device maker, internet provider or app support team. Include the exact model, software version, any error message, what you have already tried and when the problem began. Avoid sharing passwords, verification codes or private account details in a public forum.
For equipment that is hot, damaged, wet or making unusual electrical sounds, stop using it and seek qualified support. Do not open power supplies, batteries or mains-powered equipment.
Settings and menu names vary by model and software version. Use the manufacturer's current instructions for device-specific steps, and back up important files before making changes that could remove data.