Phone fast charging standards fall into two groups: the open USB Power Delivery specification, including its programmable and adjustable-voltage modes, and proprietary systems such as Samsung’s Super Fast Charging and OPPO’s SUPERVOOC, which are tied to particular chargers and phones.
Charging speed is one of several specifications covered in the guide on how to choose a smartphone, and this page sets out what each standard means.
What a fast charging standard does
A charger and a phone negotiate before power flows. The charger advertises the voltages and currents it can supply, and the phone requests a combination it can safely accept. A standard is the shared language for that negotiation.
That is why a high wattage printed on a charger does not guarantee fast charging on every phone. The charger must speak the protocol the phone expects, and the cable must be able to carry the current. Samsung makes this point in its own support guidance, saying that to use Super Fast Charging, users should check not only the charger’s power output but also whether it supports USB PD (Power Delivery) PPS (Programmable Power Supply) (Samsung).
USB Power Delivery
USB Power Delivery, maintained by the USB Implementers Forum, is the open standard most phone and laptop chargers now follow. The USB-IF explains that revision 3.1 of the specification, announced in 2021, raised the ceiling to 240W over a full-featured USB Type-C cable, where earlier versions were limited to 100W using 20V and cables rated at 5A (USB-IF).
The same page lists the new fixed voltage levels of 28V, 36V and 48V, which enable up to 140W, 180W and 240W respectively. It also describes an adjustable voltage supply mode that lets the device being powered request intermediate voltages between 15V and the maximum fixed voltage of the charger.
A phone does not need the top of that range. It uses whichever of the charger’s advertised profiles it supports, and the 240W tier is a ceiling for the specification rather than a figure phones are built to reach.
PPS and adjustable voltage
Within USB Power Delivery, phones commonly rely on a mode that lets the charger vary voltage in small steps. Samsung lists the 45W EP-T4511 charger with a PPS range of 5 to 20V at 2.25A and pairs it with Super Fast Charging 2.0, based on use with a 45W, 5A cable. For Galaxy S25 and later models, Samsung says Super Fast Charging 2.0 is supported with the 3A USB cable included with the device (Samsung).
Apple uses a related term for its newest models. Its support page says that to fast charge iPhone 18 Pro and iPhone 18 Pro Max to 50 percent in around 15 minutes, owners need Apple’s 40W Dynamic Power Adapter with 60W Max, or a comparable third-party 60W-capable adapter that uses Adjustable Voltage Supply (AVS) and supports USB Power Delivery (USB-PD) 3.2 (Apple).
The practical lesson is that the generic “PD” label is not enough on its own. Two chargers that both say 45W may differ in which voltage modes they offer, and a phone that needs a programmable mode will charge slowly on one that lacks it.
Proprietary systems
Several phone makers add their own protocols on top of, or alongside, USB Power Delivery. Samsung’s support page describes Adaptive Fast Charging at 15W over USB-A, Super Fast Charging at 25W using USB PD with PPS, Super Fast Charging 2.0 at 45W and Super Fast Charging 3.0 at 60W, the last using a USB-C PD 3.1 PPS charger (Samsung). Samsung’s support page also lists the 60W EP-T6010 adapter with a PPS range of 5 to 20V at 3A, based on use with a 60W, 3A cable (Samsung). The names are Samsung’s, but the 25W, 45W and 60W tiers are built on the open PPS mode.
OPPO lists a different mix on its phone pages. For the Find X9 Pro, the specification page shows support for up to 80W SUPERVOOC and 80W UFCS, and compatibility with 67W and below SUPERVOOC, 44W third-party UFCS, 55W PPS and 11.7W PD (OPPO). That list shows how a phone can accept several protocols at different power ceilings, falling back to a lower tier when the charger does not match.
The difference between the two groups is who defines the protocol. Proprietary names belong to one maker, while USB Power Delivery is specified by the USB-IF, which is why Apple, Samsung and OPPO all list USB-PD or PPS support alongside their own tiers.
What Apple specifies
Apple publishes adapter guidance by model. The company says iPhone 17, iPhone 17 Pro and iPhone 17 Pro Max can charge up to 50 percent in around 20 minutes with a 40W adapter or higher, while the iPhone 17e and iPhone Air need a 20W adapter or higher to reach 50 percent in around 30 minutes. For an iPhone 15 or later, it lists an Apple 18W or greater USB-C Power Adapter or a comparable third-party USB-C adapter that supports USB-PD (Apple).
Wireless charging has its own requirements. For iPhone 16, iPhone 17 and iPhone Air, Apple says to use a MagSafe Charger with an Apple 30W or greater USB-C Power Adapter or a comparable third-party USB-C adapter that supports USB Power Delivery, while iPhone 15 and earlier models can fast charge up to 15W with a MagSafe Charger and an adapter of 20W or greater (Apple).
Apple also notes that fast charging might not work in conditions that are too cold or too hot, and that charge time varies with adapter, settings, usage and environmental factors.
Cables, ports and everyday checks
A few checks prevent most disappointment. The first is the cable: Samsung’s guidance says cable requirements vary with the charger’s maximum output, and that if the cable does not meet the required specifications the charger may not deliver its maximum output (Samsung). The second is the wattage label on the adapter itself.
- Match the adapter to the protocol the phone maker lists, not only to the headline wattage.
- Use a cable rated for the power the phone maker specifies.
- Treat manufacturer charge-time claims as results from the maker’s own test conditions.
Water resistance is rated separately from charging speed, as the guide to the ip68 rating explains.
Charging support also differs across a single maker’s range. Samsung’s table of charging types lists support per model, including its folding handsets, a category examined in the guide to foldable phones, so a charger that gives one model its top speed may give a sibling a lower tier.
Frequently asked questions
Is USB Power Delivery the same as fast charging?
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USB Power Delivery is one open way to deliver fast charging. Other systems exist, and a phone may support several of them at different power levels.
Does a higher wattage charger always charge a phone faster?
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No. The phone requests the voltage and current it supports, and Samsung’s support page says a charger without PPS may not deliver Super Fast Charging even with a high maximum output.
Can any USB-C cable carry fast charging?
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Not always. Samsung says a cable that does not meet the required specifications may stop the charger reaching its maximum output.
Does temperature affect fast charging?
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Apple notes that fast charging might not work in conditions that are too cold or too hot.
