Two adapters, one answer.

Every page here ends with a pick, not a shrug. The criteria never change: watts actually delivered to your device, protocol correctness, cable requirements, physical size, and how much headroom you get per dollar spent.

The decisions people actually search for

If your question is on this list, the one-line answer is here and the full reasoning is one click away.

Which do I buy?	Short verdict
20W or 30W for an iPhone	30W. Same class of money, covers an iPad too, and GaN 30W bricks are now smaller than Apple's 20W.
5W or 20W	20W, always. It is a genuine 3× on an iPhone, not a rounding difference.
18W or 20W	Effectively a tie. Don't replace a working 18W; if you're buying new, jump to 30W.
45W or 65W	65W. It is the best watt-per-dollar tier on the market and the only one that covers laptops.
65W or 100W	65W unless you own a MacBook Pro 14″ or charge three devices at once.
100W or 140W	140W only for a 16″ MacBook Pro. It is the PD 3.1 boundary and needs an EPR cable.
PD or PPS	Buy both — every PPS charger is a PD charger. Mandatory if you own a Galaxy S Ultra.
USB-A or USB-C	USB-C. USB-A stops around 12–18W and cannot do Power Delivery at all.
GaN or silicon	GaN above 30W. Below that the size saving is too small to pay for.
One port or three	Multi-port at 65W and up, single-port for a dedicated bag or bedside brick.

The five numbers every comparison turns on

Adapters are marketed on brand and shape and decided on five specs. Peak wattage tells you the ceiling; the rail list (5V, 9V, 15V, 20V, plus 28V/36V/48V on PD 3.1) tells you whether the ceiling is reachable by your device; PPS decides whether Samsung fast-charging engages; shared-port behaviour decides what you actually get when a second cable goes in; and cable rating caps everything — 3A cables stop at 60W, 5A e-marked cables at 100W, EPR cables at 240W. Start at what wattage do I need if you don't yet know your device's draw, or USB-C Power Delivery explained for the protocol itself.

Rule of thumb that settles half of these pages: when two adapters are one class apart and priced in the same bracket, the bigger one wins — a device never draws more than it asks for, so the extra watts are free headroom for your next phone or laptop.

Where to go next

Comparisons are for narrowing two options you already have in mind. If you're starting from scratch, work down from the device with chargers by device, from the number with the wattage hub, or from the shortlists in our best-of lists. Multi-adapter desks are covered in multi-port adapters.

FAQ

Is a higher-wattage charger ever worse than a lower one?

Only in size, weight and price. Electrically it cannot be worse: USB-C devices negotiate their own contract, so a 140W adapter gives a phone the same 20W a small brick would. The one practical catch is that adapters above 100W need an EPR-rated cable to reach their top rail.

Why do these pages never quote prices?

Charger prices move weekly and vary by colour, bundle and seller. We compare price per watt and price bracket instead, which stays true, and link to Amazon where the live price is shown.

What makes two adapters genuinely different?

Delivered wattage on the rail your device uses, protocol support (PD, PPS, PD 3.1), port count and how power splits between ports, physical volume, and safety certification. Brand name is not on that list.

Do I need a new cable when I move up a wattage class?

Above 60W yes, in practice. Sustained charging over 60W requires a 5A e-marked cable, and anything above 100W requires an EPR cable rated to 240W. The adapter silently falls back to a lower rail otherwise.

Two adapters, one answer.

The decisions people actually search for

The five numbers every comparison turns on

All 30 comparisons

Where to go next

FAQ