iPhone 16 Pro Max battery life was so crazy long we tested it 3 times — here's the results

There's a lot you need to do when reviewing a phone. We run a bunch of lab tests to gauge performance and display quality; I use the cameras in the real world to test all of their new features and put them up against the best camera phones to see how well it performs; and our testers run our own home-grown battery test to see how long the handset lasts on a charge. And the iPhone 16 Pro Max's initial result was so long it delayed the rest of my review.

In case you don't know how we test the endurance of phones, we put every phone we review through the Tom's Guide battery test. This involves surfing the web over 5G at 150 nits of screen brightness. If a given device lasts more than 14 hours, it earns a spot on our best phone battery life list.

The iPhone 16 Pro Max turned in an initial run time runtime of 18 hours and 6 minutes. That blows away every other iPhone we've tested and beats the iPhone 15 Pro Max by over 4 hours.

That's so good I thought there might be something wrong. So we ran our battery test again. And again. This time the iPhone 16 Pro Max' results weren't quite as epic, turning in times of 17:11 and 17:28, but when we averaged all three together you get a very impressive result of 17 hours and 35 minutes.

To be fair, there are other phones that last longer on a charge. For example, the Asus ROG Phone 8 Pro gaming phone endured for a whopping 18:48, and the OnePlus 12R lasted for an average of 18:08. But the iPhone 16 Pro Max's runtime puts it in a solid third place overall of all recent phones we've tested.

Just in case you're wondering, the latest Google Pixel 9 phones are not close. The Pixel 9 Pro XL peaked at more than 14 hours on one test, the best average time comes from the Pixel 9 Pro at 13.5 hours.

If you want a big screen on a budget, it's worth noting that the iPhone 16 Plus lasted 16:29 in the Tom's Guide battery test. That's about an hour behind the iPhone 16 Pro Max but that's still quite an impressive battery life test result.

So what about the regular iPhone 16 Pro? In our testing that handset lasted a good-but-not-stellar 14:07. So if you want the longest possible battery life on an iPhone the Pro Max is the way to go. However, there are other benefits to the iPhone 16 Pro, including it's more compact size and cheaper starting price. See our iPhone 16 Pro vs iPhone 16 Pro Max comparison to help you decide.

The bottom line if that the iPhone 16 Pro Max is a battery life giant, even if it made our lab testers work overtime.

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