Does your phone charge as fast as advertised?

I tested three fast-charging smartphones — the iPhone 17 Pro Max, Samsung Galaxy S26 Ultra and OnePlus 15 — using both OEM chargers and a third-party Anker setup. The OnePlus 15 includes a power plug; the other two ship with only a cable. Apple sells a 40 W Dynamic Power adapter for $39, Samsung a 45W travel adapter with a magnetic wireless charging puck for $71.25, and I used an Anker Prime GaN charger with an Anker bio cable.

Battery capacities and advertised wired charging: the iPhone 17 Pro Max has a 5,088 mAh battery rated for 40W, the Galaxy S26 Ultra a 5,000 mAh battery rated for 60W, and the OnePlus 15 a 7,300 mAh silicon carbon battery advertised at 120W. In practice, a phone's peak wattage is not its charging speed for most of the charge.

The OnePlus charger never approached 120W, peaking at 46W and spending its charge time between roughly 20% and 40% battery. The Anker pairing often charged the OnePlus and Samsung phones faster than their own chargers.

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