Charging time depends on your charger, cable, and iPhone model

A standard iPhone charges from zero to full in roughly 30 minutes to 2 hours, depending on which charger you use. The newer your iPhone and the more powerful your charger, the faster it goes. An iPhone 15 with Apple's 20-watt charger reaches 50 percent in about 30 minutes. An older iPhone 12 with the same charger takes closer to 45 minutes to reach 50 percent. If you use a basic 5-watt charger — the oldest type — expect a full charge to take 3 to 4 hours.

The speed also changes based on what your phone is doing while it charges. If you are using the phone, watching video, or running apps, charging slows down noticeably. A phone left alone and locked charges much faster than one you are actively using.

Key Takeaways

  • Fast charging with a 20-watt or higher charger reaches 50 percent in 25 to 35 minutes, but the last 50 percent takes much longer.
  • Using your iPhone while it charges slows the process by 20 to 40 percent compared to leaving it locked.
  • Older iPhones and basic 5-watt chargers add an hour or more to total charging time.
  • Battery temperature affects speed — a phone that gets warm during charging will slow down to protect the battery.

How charger wattage affects speed

The wattage of your charger is the single biggest factor. Apple sells chargers in 5-watt, 20-watt, 30-watt, and higher power ratings. A 5-watt charger is the slowest and comes with older iPhones. A 20-watt charger is the current standard and is what most people should use. A 30-watt or higher charger is faster still, though the difference becomes smaller as you go higher.

Here is what you can expect with common chargers on an iPhone 15: a 5-watt charger takes about 3 hours for a full charge; a 20-watt charger takes about 1 hour 20 minutes; a 30-watt charger takes about 1 hour. The jump from 5 to 20 watts saves you nearly 2 hours. The jump from 20 to 30 watts saves you only 20 minutes. This is because iPhones slow down charging as the battery fills — the last 20 percent always takes longer than the first 20 percent, no matter what charger you use.

You do not need to buy the most powerful charger available. A 20-watt charger is fast enough for daily use and is gentler on your battery over time. Higher wattage chargers are useful only if you regularly need a full charge in under an hour.

Why the last 50 percent takes longer than the first 50 percent

Fast charging works by sending a lot of power into the battery when it is empty or half-full. Once the battery reaches about 50 percent, the iPhone automatically slows the charging speed to protect the battery from heat and wear. This slowdown is intentional and keeps your battery healthy for years.

This is why you might see your phone charge very quickly from 0 to 50 percent, then seem to stall from 50 to 100 percent. With a 20-watt charger, you might hit 50 percent in 30 minutes but need another 50 minutes to reach 100 percent. The phone is protecting itself, not malfunctioning.

If you only need your phone to half-charge — enough for a few hours of use — you can unplug it after 30 to 40 minutes and get the speed benefit without waiting for the full charge. This is also slightly better for long-term battery health than charging all the way to 100 percent every single day.

How using your phone while charging affects speed

Using your iPhone while it charges makes the process slower. Apps, video playback, and even just scrolling draw power from the battery at the same time the charger is trying to fill it. The net effect is that the battery fills more slowly. On average, using your phone while charging adds 20 to 40 percent more time to a full charge.

The slowdown is worse with demanding tasks. Streaming video or playing a game while charging might add an hour to your total time. Checking messages or reading while charging adds 15 to 20 minutes. If you need a fast charge, lock your phone and set it down.

You can also turn on Low Power Mode while charging if you want to speed things up slightly. This reduces background activity and makes the charger's power go further toward filling the battery rather than running apps.

Temperature and charging speed

iPhones charge slower when they get warm. If your phone feels hot to the touch while charging, the battery is protecting itself by reducing charging speed. This is normal and happens most often when you are using the phone while charging, or when the room temperature is very warm.

You can speed up charging by removing the phone from its case while plugged in, which lets heat escape more easily. If your phone is very warm, unplug it for a few minutes and let it cool down. Charging will resume at full speed once the temperature drops.

Extreme cold also slows charging, though less noticeably than heat. If you bring a very cold iPhone indoors to charge, it may charge slowly until it warms up to room temperature. This is not a problem — the phone is straightforward being cautious.

Wireless charging versus wired charging

Wireless charging is slower than wired charging. A wireless charger typically delivers 7.5 to 15 watts of power, depending on the model. This means a full charge takes 2 to 3 hours, compared to 1 to 1.5 hours with a wired 20-watt charger. Wireless charging is convenient for overnight charging or when you want to set the phone down without plugging in a cable, but it is not the choice for a quick top-up.

Wireless chargers also generate more heat than wired chargers, which means the iPhone slows down charging sooner to protect the battery. If you use wireless charging daily, your battery may wear out slightly faster than if you use wired charging. For occasional use or overnight charging, wireless is fine. For regular fast charging, a wired charger is better.

Charging time by iPhone model

Newer iPhones charge faster than older ones because they support higher wattage chargers. An iPhone 15 or 15 Pro with a 20-watt charger reaches 50 percent in about 30 minutes. An iPhone 14 takes about 35 minutes. An iPhone 13 takes about 40 minutes. An iPhone 12 takes about 45 minutes. An iPhone 11 or older takes about an hour to reach 50 percent with the same charger.

The difference comes down to the battery size and the charging technology inside the phone. Newer models have larger batteries but also more efficient charging circuits, so the net effect is similar charging times. If you have an older iPhone, upgrading to a newer charger will help somewhat, but the phone itself limits how fast it can charge.

Frequently Asked Questions

Is it bad to leave my iPhone plugged in overnight?

No. Modern iPhones stop charging at 100 percent and do not draw power from the charger after that point. Leaving your phone plugged in overnight will not damage the battery. However, if you charge to 100 percent every single day and leave it at 100 percent for many hours, the battery will wear out slightly faster over years. For daily use, overnight charging is fine.

Why does my iPhone charge slower than it used to?

Battery capacity decreases over time as you use your phone. After 500 to 1,000 full charge cycles, an iPhone battery holds less charge and may charge slightly slower. This is normal wear. If charging has become much slower suddenly, restart your phone or try a different cable and charger to rule out a hardware problem.

Does a third-party charger charge slower than Apple's charger?

Not necessarily. Any charger rated for the same wattage will charge at the same speed. A third-party 20-watt charger charges just as fast as Apple's 20-watt charger. The difference is in build quality and safety — Apple chargers meet strict standards, and some third-party chargers do not. Stick with chargers from reputable brands or Apple's own products.

Can I use a faster charger than the one that came with my iPhone?

Yes. iPhones are designed to work safely with chargers faster than the original. A 30-watt charger will charge your iPhone faster than a 20-watt charger, with no damage to the battery. The phone itself controls how much power it draws, so using a more powerful charger is safe.

Does charging to 80 percent instead of 100 percent really help the battery?

Yes, slightly. Keeping your battery between 20 and 80 percent most of the time slows the rate at which it wears out. If you charge to 100 percent every day and leave it there for hours, the battery will degrade faster than if you stop at 80 percent. For most people, this difference is small enough that daily convenience matters more. If you want maximum battery lifespan, enable Optimized Battery Charging in Settings, which automatically stops charging at 80 percent overnight.