Low Power Mode does not slow down how fast your phone charges from a wall outlet or car charger

When you plug your phone in while Low Power Mode is on, it charges at the same speed as it would with Low Power Mode off. The charger itself determines the charging speed — not the phone's power settings. Low Power Mode changes what your phone does while it is running, not how quickly electricity flows into the battery.

What Low Power Mode actually does is reduce the power your phone uses once it is charged. It dims the screen, slows background app activity, and limits processing speed. None of these changes affect the charging circuit that pulls power from the wall.

Key Takeaways

  • Low Power Mode does not change charging speed from a wall outlet, car charger, or wireless charger.
  • Your charger's wattage and your phone's charging port determine speed — Low Power Mode has no effect on either.
  • Low Power Mode reduces battery drain while your phone is in use, which means the battery level rises faster relative to how much power you are using.
  • If your phone charges slowly, the cause is the charger, the cable, the port, or a hardware issue — not Low Power Mode.

Why the confusion exists

People often notice their battery percentage climbs faster when Low Power Mode is on. This is real, but it is not because charging is faster. It is because the phone is using less power at the same time it is receiving power. If your phone normally drains 5% per hour while idle and charges at 10% per hour, the net gain is 5% per hour. With Low Power Mode on, the phone might drain only 2% per hour, so the net gain becomes 8% per hour — even though the charger is still delivering the same 10%.

The battery percentage rising faster feels like faster charging, but the charger is doing the same work. You are just losing less power to background processes.

What actually controls charging speed

Your charger's wattage is the primary factor. An iPhone 15 with a 20-watt charger will charge faster than the same phone with a 5-watt charger, regardless of Low Power Mode. An Android phone with a 65-watt charger will charge much faster than either. The phone's charging port and internal charging circuit also matter — some phones support faster charging than others, and a damaged port will slow everything down.

Low Power Mode does not touch any of these components. It only changes what happens after the power enters the battery.

When charging speed actually slows down

Charging does slow down in a few real situations, and Low Power Mode is not one of them. If your phone is hot — from heavy use, direct sunlight, or a case that traps heat — it will throttle (reduce) charging speed to protect the battery. This happens whether Low Power Mode is on or off. If your cable is damaged, your port is loose, or your charger is underpowered, charging will be slow. If your battery is old and degraded, it may not accept a full charge rate anymore.

You can check your actual charging speed on most phones. On iPhone, go to Settings > Battery > Battery Health & Charging and look for the peak charging wattage. On Android, apps like Ampere (free) or AccuBattery (free) show real-time wattage. If the number is much lower than your charger's rated wattage, the problem is hardware, not Low Power Mode.

Should you use Low Power Mode while charging

There is no downside to leaving Low Power Mode on while your phone charges. It will not slow the charging process, and it will reduce the heat your phone generates — which is actually good for the battery. Heat is what degrades batteries over time, so if you are charging overnight or during a long session, Low Power Mode can help keep the battery cooler.

The only reason to turn Low Power Mode off while charging is if you want your phone to run at full speed while you use it. Once the phone is fully charged, Low Power Mode stops affecting anything anyway.

How to check if your charger is the problem

If your phone charges slowly even with Low Power Mode off, test your charger with a different device if you have one. If that device charges normally, your phone's port or battery is the issue. If the other device also charges slowly, your charger is underpowered or damaged. Try a different cable with your charger — a frayed or bent cable is a common culprit and costs less to replace than a new charger.

If you have access to a faster charger (borrow one from a friend or try one at a store), plug your phone in for five minutes and check the wattage. If it jumps to a much higher number, your original charger is the bottleneck. If it stays low, the problem is in your phone.

Frequently Asked Questions

Does Low Power Mode drain the battery faster when I am using my phone?

No. Low Power Mode reduces battery drain by limiting background activity and screen brightness. Your battery will last longer in Low Power Mode than with it off, even if you are actively using the phone.

Will turning off Low Power Mode make my phone charge faster?

No. Charging speed depends on your charger and phone hardware, not on Low Power Mode. Turning it off will not change how many watts flow into the battery.

Can Low Power Mode damage my battery if I charge with it on?

No. Low Power Mode actually reduces heat while charging, which is better for battery health. There is no risk to charging with Low Power Mode enabled.

Why does my phone charge slowly even though I have a fast charger?

Check the cable first — a damaged cable is the most common cause. Then test the charger with another device. If that device charges normally, your phone's port or battery needs inspection. If the other device also charges slowly, the charger itself may be faulty.