There aren’t worlds between the iPhone 17 Pro and the 18 Pro. Plenty of you still tell me you’re itching to upgrade. There is one measurable difference, though, and that’s charging speed. So I put both phones side by side, charged them under identical conditions and wrote down the battery level every 10 minutes.
How I Tested
Both iPhones started at 10% battery. I charged in the basement, because the temperature there is low and stable. That matters: when an iPhone gets warm it throttles charging, and the measurement wouldn’t be comparable anymore. I checked the level after 10, 20 and 30 minutes.
I picked each charger to match the phone’s maximum. The iPhone 17 Pro Max takes 40W at most, so I used an Anker 45W charger. It can’t go higher. The iPhone 18 Pro Max can take up to 60W, with about 53W actually arriving, so I used Apple’s new charger, the same one I used to reproduce Apple’s 50%-in-15-minutes claim.
The Results
iPhone 17 Pro Max: 36% after 10 minutes, 57% after 20, 71% after 30.
iPhone 18 Pro Max: 45% after 10 minutes, 73% after 20, 86% after 30.
That gives the 18 Pro Max this lead:
✓ After 10 minutes: 9 percentage points
✓ After 20 minutes: 16 percentage points
✓ After 30 minutes: 15 percentage points
Why the Gap Is Biggest at 20 Minutes
The shape of the curve is the interesting part. The lead grows from 9 to 16 percentage points and then slips back slightly to 15. That’s because every iPhone pulls back on power toward the end to protect the battery. After 30 minutes the 18 Pro Max is already at 86% and deep into that phase, while the 17 Pro Max at 71% is still climbing a bit faster. So if you top up quickly while you’re out, you’ll notice the difference mostly in the first 20 minutes. That’s exactly where it’s largest.
Important: It Doesn’t Work Without the Right Charger
Keine Produkte gefunden.
You’ll only reach the 18 Pro’s numbers with a charger whose adjustable voltage the iPhone actually uses, meaning AVS. With a charger that doesn’t support it, or one whose AVS the iPhone refuses, you charge noticeably slower. I’ve already tested which chargers work and which don’t. To check whether your own charger is fast enough, use my free Charge Check.
Some Perspective
Apple doesn’t win this comparison against Android. Some Xiaomi phones charge at far higher wattage and are full much sooner. Measured against what Apple has delivered in recent years, though, the jump from the 17 Pro to the 18 Pro is clear. With today’s battery tech, 16 percentage points after 20 minutes is not a detail.
So Is It Worth Upgrading?
Honestly, not for charging speed alone. If you have a 17 Pro, you have a very good phone that still hits 71% in 30 minutes. But if you were already leaning toward an upgrade and wanted an argument, here’s one you can actually measure. And if you’re coming from an older iPhone, you get the difference for free.
More iPhone 18 Pro Tests
If your new iPhone has already arrived, protect it properly right away. You’ll find my winners among the iPhone 18 Pro cases and the iPhone 18 Pro screen protectors. If you’re waiting for the foldable iPhone, see my tests of iPhone Duo cases and iPhone Duo screen protectors.