Phone battery draining fast: causes and what to do

A battery that drains fast almost always comes down to one of three things: an app using too much, power-hungry settings (screen, location, weak signal) or a worn-out battery. Figure out which one applies to you before changing everything.

In this article

1. 1. Find out what’s draining it
2. 2. The settings that save the most
3. 3. Myths that don’t help
4. 4. Check your battery health
5. FAQ

1. Find out what’s draining it

• Android: Settings › Battery › Battery usage (the name varies a bit between brands).
• iPhone: Settings › Battery, and check the per-app list for the last 24 hours or 10 days.

An app that shows up at the top even though you barely use it (especially with a lot of “background” usage) is the suspect. Update it, restrict its background usage or uninstall it.

2. The settings that save the most

1. Auto-brightness on and a short screen timeout (30 seconds to 1 minute).
2. Dark mode, especially on OLED/AMOLED screens.
3. Location: allow it only for apps that need it, and set them to “Only while using the app”.
4. Weak signal drains a lot: in places with poor reception, the phone pushes its antenna hard. At home, use Wi-Fi. If 5G is spotty in your area, choose 4G.
5. Screen refresh rate: on Android phones with 120 Hz, the Standard/60 Hz mode saves power.
6. Battery saver: turn it on when the battery is low or when traveling (Low Power Mode on iPhone).

3. Myths that don’t help

• Closing all open apps all the time: the system already manages this, and relaunching apps from scratch uses more power.
• “Calibrating” by draining to 0%: lithium batteries don’t need this, and frequent full discharges wear them out faster.
• “Battery saver” apps: they usually show ads and use more power than they save.

4. Check your battery health

Batteries lose capacity over time (usually after 2 to 3 years of daily use).

• iPhone: Settings › Battery › Battery Health & Charging. Below 80%, a replacement brings your battery life back.
• Android: many models show it under Settings › Battery or in the manufacturer’s app (such as Samsung Members › Diagnostics).

Replace the battery at an authorized service provider: third-party batteries may last less and be less safe.

FAQ

My battery started draining fast after an update.

For the first few days after a major update, the system reorganizes data and photos, and uses more power. If it continues after a week, check which app is at the top of the usage list.

My phone is also getting hot.

Heat and fast battery drain usually have the same cause. See phone overheating.