Why Is My Phone Charging Slowly?
The number printed on a charger is its maximum. What your phone actually receives depends on the cable, the phone's own limits, temperature and what you are doing while it charges.
The usual causes
- The cable. A worn or thin cable can cut fast charging down to a few watts even with a good charger.
- The charger. Old 5 W adapters, car chargers and laptop USB ports are often much slower than a wall charger.
- Heat. Phones slow charging when the battery gets warm to protect it.
- Using the phone. Games, video and navigation use power while charging, so less goes into the battery.
- Near full. Charging naturally slows after about 80%.
Measure instead of guessing
- Charge to below 80% and let the phone cool down.
- Open Cellsense and tap Test charging speed, then plug in.
- Keep it connected for 30 seconds. Cellsense averages 30 readings of current and voltage.
- Name the charger (for example "Bedroom 25W") and save.
- Repeat with another cable on the same charger, then another charger with the same cable.
The History tab sorts your chargers fastest first. If one cable is far slower on every charger, replace the cable.
Reading the rating
Under 7.5 W is Slow, 7.5 to 15 W is Normal, and 15 W or more is Fast. Values vary by phone model, so compare chargers on the same phone.