Buying guide
What wattage charger do I need for my phone?
Quick answer
For most phones, a 20W–30W USB-C Power Delivery (PD) charger gives full fast-charging speed. Samsung Galaxy Ultra models need a 45W charger with PPS for their fastest mode. A higher-watt charger is safe: the phone only draws what it supports.
Key takeaways
- 20W USB-C PD is the minimum for fast charging on iPhone.
- 25W–45W with PPS unlocks Samsung's Super Fast Charging.
- Higher-watt chargers are safe — phones negotiate the power they need.
- Your cable matters: use a USB-C cable rated for at least 60W.
How does fast charging work?
Modern phones use USB Power Delivery (PD), a standard that lets the phone and charger agree on a voltage and current before power flows. Samsung and Google phones also use PPS (Programmable Power Supply), an extension of PD that adjusts voltage in small steps to reduce heat. If both ends support the same standard, you get fast charging; if not, the phone falls back to slower, standard charging.
Which charger should I buy for my phone?
| Phone | Recommended charger |
|---|---|
| iPhone 15, 16, 17 (USB-C) | 20W–35W USB-C PD |
| iPhone 14 and earlier (Lightning) | 20W USB-C PD + USB-C to Lightning cable |
| Samsung Galaxy S / A series | 25W USB-C PD with PPS |
| Samsung Galaxy Ultra | 45W USB-C PD with PPS |
| Google Pixel | 30W USB-C PD with PPS |
A dual-port charger like a 35W GaN model is a good all-rounder: it fast-charges one phone, or two devices at once at a shared lower speed.
Is a higher-watt charger safe for my phone?
Yes. A 65W laptop charger will not push 65W into a phone. Power Delivery chargers only supply what the device requests, so a bigger charger simply has headroom. What matters for safety is buying certified chargers from reputable sellers, not the wattage number.
Does the cable affect charging speed?
It can. Most USB-C to USB-C cables carry up to 60W, which is plenty for phones. Very cheap or damaged cables may fall back to slow charging. Braided cables last longer when they are bent and coiled every day.
Frequently asked questions
Can I use my iPad charger on my iPhone?
Yes. iPad USB-C chargers are usually 20W–35W Power Delivery, which fast-charges iPhones safely.
Why is my phone charging slowly with a fast charger?
Check the cable, make sure it is plugged directly into the charger (not a hub), remove thick cases that trap heat, and confirm the charger supports PD (and PPS for Samsung).
Is wireless charging slower than wired?
Usually. Magnetic Qi2 and MagSafe-compatible chargers run at about 15W, while wired USB-C PD charging is typically 20W or more.