The Hidden iPhone 13 Pro Max Bonus Feature Apple ‘Forgot’ to Tell Us About

Although both of this year’s iPhone 13 Pro models once again feature the same cameras and photographic capabilities, the iPhone 13 Pro Max distinguishes itself with longer battery life, since the larger phone can pack in a larger power cell. However, it looks like the larger 6.7-inch iPhone 13 Pro Max has another trick up its sleeve: It supports higher-wattage fast charging than any other iPhone model, capable of charging at speeds of up to 27 watts.

The faster charging speeds were revealed in a new series of tests performed by ChargerLAB, which found that the largest iPhone 13 model would draw 27 watts of power when plugged into a compatible USB-C power adapter.

This is an increase over its predecessor, the iPhone 12 Pro Max, which charged at the more Apple-standard 20W speeds. Technically speaking, the iPhone 12 could get slightly faster with an appropriate charger, clocking in at around 21-22W, but that’s a negligible difference in practical terms.

Plus, the standard USB-C adapter that Apple sold for the iPhone 12 was only rated as 20W to begin with, which was already an increase over the 18W adapter that came bundled with the iPhone 11 Pro and iPhone 11 Pro Max back in 2019.

Notably, these faster charging speeds are only available on the iPhone 13 Pro Max.

ChargerLAB told MacRumors that the iPhone 13 Pro does max out at 23W, so it’s slightly better than last year’s iPhone 12 models, but that’s not a significant enough boost to really care about.

It’s also worth keeping in mind that, just like fast charging at lower speeds, you’re not going to get the full 27 watts for the entire charging cycle.

To preserve battery health, most electronics that support fast charging slow down to more normal charging speeds as the battery nears full capacity, and the iPhone is no exception.

For example, even the iPhone 8, which was the first model to support any kind of fast USB-C charging, slowed charging speeds down once the battery reached 50%, and then slowed down again for the last 80-100% top-up. In practical terms, this meant you could go from a dead battery to 50% in 30 minutes, but you’d still be waiting almost another hour for a full charge.

We’ve seen the same kind of charging curve in subsequent iPhone models, even after last year’s boost to 20W charging. We suspect the main reason Apple is increasing the charging speeds is to make up for the higher-capacity batteries in newer iPhones.

In other words, the 27W charging doesn’t necessarily mean that the iPhone 13 Pro Max will charge to 100% faster than the iPhone 12 Pro Max did, but at least you won’t have to worry about it charging more slowly.

Testing by Twitter user and leak reporter DuanRui also revealed that with a proper 30W USB-C charger, the iPhone 13 Pro Max maintained 26W of current for about 27 minutes, which, from his charts, seems to represent approximately the 50% charge point.

Subsequently, it took another 59 minutes to fully charge, which works out to 86 minutes in total.

Tests performed by AppleInsider revealed that the iPhone 13 Pro Max only appears to start charging at 27W after the battery hits about 10% capacity, and drops to around 23 watts once it hits 40 percent. The report didn’t specify what happens at the 50% and 80% marks, although we suspect that it ramps down to the USB-standard 10-12W speeds, just like all previous iPhone models.

If you want the fastest charging speeds for your iPhone 13 Pro Max, you’ll need to make sure you purchase the right adapter, as none of the standard iPhone wired or wireless chargers will get anywhere near 27 watts. Get Apple’s 30W fast charger here.

Specifically, all the iPhone 13 models charge wirelessly at the same speeds as their iPhone 12 counterparts, which is 15W if you’re using an officially certified MagSafe adapter, or 7.5W with a standard Qi wireless charger — which includes so-called MagSafe-compatible accessories.

So, it’s no surprise that you’ll need to use wired charging to get the fastest possible speeds, and to be fair, that’s nothing new. However, this year, Apple’s standard 20W USB-C adapter is no longer the best one you can buy if you have an iPhone 13 Pro Max and want to charge at the fastest possible speeds.

To get the full 27W charging speeds from your iPhone 13 Pro Max, there’s a chance you’ll need a USB-C power adapter that supports the USB-PD (Power Delivery) spec at 9 volts and 3 amps (9V/3A).

We’ve already seen that Apple’s original 29W USB-C power adapter won’t fast charge many of its newer devices, although it remains unclear whether this applies to the iPhone 13 models.

The problem is that this original adapter gets its 29 watts of power from a now-outdated combination of 14.5 volts at 2 amps, which isn’t supported by many newer devices, such as Apple’s Magic Keyboard for the iPad Pro or even the MagSafe Duo, which run only at 9 volts.

These other voltages have traditionally been supported on the iPhone and iPad, but we don’t have any information yet on whether that’s still the case with this year’s iPhone lineup.

To be fair, Apple discontinued that adapter back in 2018, replacing it with a newer 30W adapter that meets the current 9V USB-PD spec, but it’s also an adapter that many Apple fans may still have lying around their home or office.

If you own a modern MacBook, you can also use any of the USB-C adapters that are included with those. Even the now-discontinued 87W USB Power adapter that was bundled with the 15-inch MacBook Pro supports the 9V/3A power profile, as do the current 61W and 96W adapters.

In the end, almost any modern USB-C power adapter should provide more than enough current if you’re only concerned about charging your iPhone overnight, and even a standard Qi-compatible 7.5W wireless charger can fully juice up an iPhone 13 Pro Max while you sleep.

If you’re somebody who is frequently on the go, however, it’s understandable why you may want an adapter the offers the fastest charging speeds possible, in which case the 30W Apple adapter may be worth the splurge.