iPhone 18 Pro: 50% in 15 Minutes? My Test with Apple’s Charger and AVS
Apple promises 50% battery in just 15 minutes on the iPhone 18 Pro. My iPhone 17 Pro Max takes 20 minutes for that, so it would be a big jump. I measured the claim on the iPhone 18 Pro Max, sticking strictly to Apple’s rules. The result: I didn’t hit 50%. On top of that, a 100-watt charger turned out to be a bad buy, even though it supports the technology you need.
What the Fine Print Says
According to Apple’s footnote, 50% in 15 minutes only applies under certain conditions. The first is a starting battery level of 0%. Nobody does that in real life, but for a fair test I had to. The second is Apple’s 40W Dynamic Power Adapter, which can briefly deliver up to 60W. If you don’t have that charger, Apple says you need one with USB Power Delivery 3.1 or later and adjustable voltage supply.
That adjustable voltage is called AVS, short for Adjustable Voltage Supply. The problem is that most manufacturers don’t mention in the product description whether their charger supports AVS. The only way to prove it is with a USB meter that reads the protocol.
AVS Explained Simply
AVS isn’t an Apple invention. It’s part of the USB standard, and what’s new is simply that the iPhone now uses it. Samsung has been doing something similar with PPS for years. Here’s the idea: the iPhone tells the charger exactly what voltage it needs, and the two keep adjusting as it charges.
Chargers used to deliver voltage in fixed steps, like a staircase. Those steps never matched exactly, so the iPhone had to step the voltage down internally. That creates heat, and the warmer the iPhone gets, the slower it charges. AVS removes that detour. Apple also says the iPhone 18 Pro can charge at up to 60W, instead of 40W like the 17 Pro.
How I Tested
The iPhone was completely empty each time. Before each run I measured the temperature of the back and brought the iPhone to about 26 to 28°C. I charged with the original 3-amp USB-C cable from the iPhone box. A USB meter between the cable and the iPhone showed the power and the protocol. I started the timer and the power at the same moment and cut the power after exactly 15 minutes.
Test 1: Apple’s 40W Dynamic Power Adapter
- The 40W Dynamic Power Adapter with 60W Max is uniquely designed to dynamically deliver up to 60W of output, providing a powerful boost in charging speeds.
- With Dynamic Power, you get many of the same benefits of higher-wattage chargers in a compact, pocket-size form factor to make charging at home, in the office, or on the go faster and more convenient than ever.
- For fast charging, pair the Dynamic Power Adapter with iPhone 17 models (50 percent battery in around 20 minutes) or iPhone Air (50 percent battery in around 30 minutes).
- Compatible with USB-C–enabled devices. Charging cable sold separately.
The charger itself has a cool new detail: the prongs disappear into the housing and pop out at the press of a button. While charging, the meter showed AVS right away. Power climbed to 48W, then 51W, and briefly 52W. I never saw 60W. Toward the end it dropped to 42W, then 38W and finally 34W.
After 15 minutes the battery was at 47%, with the back at 37°C. So I narrowly missed 50%. I suspect room temperature played a role. As far as I know, Apple measures at 16 to 22°C, and my room was closer to 22°C. In a cooler room, 50% might have been possible.
Test 2: Ugreen Nexode Pro 100W
- Smart Digital Display with Touch Control: The visible monitoring wall charger allows easy switching between real-time charging data via its touch panel. The displayed data includes total output power, individual port power, charging protocol (PD/QC), real-time device battery level and charger core temperature, enabling you to grasp all charging details at a glance and avoid overcharging risks
- 100W PD High-Speed Fast Charger: UGREEN GaN USB C charger delivers 100W max PD fast charging, rapidly powering slim laptops, smartphones and tablets. This USB C laptop charger charges Macbook Pro M4 14'' to 54% in just 30 minutes, eliminating the need for bulky original laptop chargers
- 5-in-1 Multi Port USB C Charging Adapter: The 100W PD fast charger features 4 USB-C ports + 1 USB-A port, supporting simultaneous fast charging of up to 5 devices at once; it has intelligent power distribution technology that avoids power competition between devices, ensuring stable charging for all connected electronics
- Multi-Layer Safety Certified: UGREEN reliable protection PD fast charging adapter complies with local electrical safety standards, built-in over-voltage, over-current, over-heat, short-circuit and over-charge protection; the intelligent temperature control system automatically adjusts power when overheating, safe for all-day and overnight charging for all USB-C/USB-A enabled devices
- Portable & Fire-Resistant Design: UGREEN 100W PD charger block features a foldable plug, making it an excellent choice for road trips and daily commutes; premium PC material and a 94-V0 fire-resistant shell ensure its durability
The Ugreen Nexode Pro supports AVS, and I confirmed that with the meter beforehand. So I hoped it could replace Apple’s charger, especially since a lot of people already have one like it at home. But during charging the meter showed no AVS. The iPhone simply won’t accept AVS from the Ugreen. I don’t know why. According to Apple, a charger with USB PD 3.1 and adjustable voltage should be enough, and that’s exactly what the Ugreen is.
Without AVS, the Ugreen never went above about 43W. After 15 minutes the battery was at 44%, with the back at 36°C.
What the Numbers Show
The difference in battery level is small, just 3 percentage points. Something else is more interesting. Apple’s charger delivered over 10 watts more and only got about 1 degree warmer. That’s exactly the benefit of AVS: more power with hardly any extra heat.
In practice, the iPhone 18 Pro Max also doesn’t seem to charge at 60W. Even with Apple’s own charger it topped out at around 52 to 53W, and ChargerLab measured a 53W peak as well. According to Apple, the Pro and Pro Max charge the same.
By the way, you can find out how fast your own iPhone charges on your charger with my free Charge Check.
Verdict: Is a Third-Party AVS Charger Worth It?
Right now, no, at least not the Ugreen Nexode Pro. If you bought it only to get your iPhone 18 Pro to 50% in 15 minutes, send it back. I’m returning mine too. As a charger it’s still not bad, and 44% in 15 minutes is a solid result. But Apple’s charger is the only one in the test where the iPhone actually uses AVS. Even Apple didn’t hit 50% for me, though. 47% is still a good result.
I’m now looking for a charger from another brand where the iPhone does accept AVS. That will get its own video.
More iPhone 18 Pro Tests
If you want to protect your new iPhone, you’ll find my test winners among the iPhone 18 Pro cases and iPhone 18 Pro screen protectors. If you’re waiting for the foldable iPhone, check out my tests of iPhone Duo cases and iPhone Duo screen protectors.