USB-C Power Delivery Explained: What a Charger Can Actually Do

USB-C names the connector

USB-IF’s language guidelines, in the file dated 20 March 2023, say USB Type-C is a type of connector. The recommended messages are about the slim shape, a robust fit for laptops and tablets, and a reversible plug. You can insert either face, and either end of a USB-C to USB-C cable. USB Type-C and USB-C are registered trademarks of USB Implementers Forum for that connector. USB-IF also says “USB-C” is acceptable when you need the shorter name.

The same guidelines draw two hard lines. USB Type-C is not USB 3.2 or USB4. The connector specification supplements those data specifications. USB Type-C is not USB Power Delivery. Power Delivery is the protocol and hardware solution that increases USB power up to 240W. Device makers can add USB Power Delivery, USB4, or USB 3.2. None of the three is required for a product to be a USB Type-C product.

That is why a search for a USB-C charging type has to leave the plug outline and go to the label. The guide to telling a USB-C plug from USB-A, Micro-USB, and Lightning stays with the shape. This page stays with the power contract.

The oval plug is the connector. The photo does not show a power contract, a data rate, or a brand.

The Type-C cable and connector specification page describes the same object: a smaller connector for thinner platforms, with a reversible plug orientation. It says the connector supports scalable power and performance. Scalable means the product designer chooses what to implement. It does not mean every port offers every voltage below.

What USB Power Delivery changed in 2021

The USB charger page describes USB Power Delivery as flexible power along with data over a single cable. Before the 2021 update, USB PD was limited to 100W using 20V and USB Type-C cables rated at 5A. The announcement of USB PD Revision 3.1, dated 26 May 2021, enables up to 240W over the USB Type-C cable and connector. USB-IF says the USB Type-C specification was updated to Release 2.1 to define the 240W cable requirements.

The announcement lists the fixed voltages in two groups.

Read the two columns as two sentences USB-IF actually published. The announcement says 28V is the fixed voltage above 100W, 36V above 140W, and 48V above 180W. The charger page says those three fixed voltages enable up to 140W, 180W, and 240W respectively. This page does not convert those watts back into a current and then call that current a cable rating.

Texas Instruments’ note in the same announcement says the revision includes the capability to provide up to 48V and 240W. That sentence is a member comment on the specification. It is not a measurement of a charger on a desk.

The announcement also says the new architecture uses a stricter power negotiation so the higher range can be used safely, and that products in the 100W to 240W range follow the safety specifications of each country where they are sold. USB-IF does not name a single consumer test you can repeat at home in that paragraph. Treat a damaged plug, a hot housing, or a scorched port as a reason to stop using that part.

Two other behaviors on the charger page matter when you are choosing a brick. Power direction is no longer fixed, so the product that has the power, host or peripheral, can supply it. USB-IF’s own example is a monitor that takes wall power and then powers or charges a laptop while the laptop still displays. Each device takes only the power it requires, and can take more when the application needs it. Power Delivery is designed to coexist with USB Battery Charging. This page does not restate Battery Charging currents, because those numbers are not on the pages saved for this update.

A simplified sequence for the negotiation USB-IF describes. The cable still has to be allowed to carry the agreed mode. This is not a pin diagram.

Adjustable voltage stays inside the charger’s maximum

The 26 May 2021 announcement adds an adjustable voltage mode. The powered device can request a voltage from 15V up to one of three maxima, 28V, 36V, or 48V, depending on the power available, in steps of 100 mV. The charger page describes the same idea as intermediate voltages between 15V and the maximum fixed voltage that charger offers.

That mode is the one USB-IF defined for the higher range. If a phone’s own page names PPS, or prints a peak for that phone, leave the peak on the page that printed it. Use the PPS charging guide for the name PPS, the iPhone USB-C charger and cable guide for an iPhone, and the Samsung and Android fast-charger guide for those phones. Copying a handset peak onto this explainer would mix a model line with the specification.

The cable logo is its own limit

Use the 60 W versus 240 W cable and e-marker identification guide to distinguish the visible power label, the current capability and EPR support, including older 100 W cables.

USB-IF’s cables and connectors page says cables do not all have the same capabilities, and a certified cable does not add capabilities to the charger or the computer. For the compliance program, every USB-C to USB-C cable category must be labeled with a power capability of 60W or 240W. Data-rate marks are separate. The page’s worked marking case is a USB 20Gbps USB-C to USB-C cable that supports 20V at 3A: it must carry the combined 20Gbps/60W logo. A USB 2.0 USB-C to USB-C cable needs the power icon. The USB 2.0 data logo on that cable is optional.

Worked example. Power = voltage × current. For the cable USB-IF describes, 20 V × 3 A = 60 W, which is why that cable’s power logo is 60W. The same arithmetic explains the older ceiling in the PD announcement: 20 V × 5 A = 100 W, matching “100W using a solution based on 20V using USB Type-C cables rated at 5A.” The 5A figure belongs to that pre-3.1 description. It is not a rating this page assigns to every cable in a drawer.

A USB 2.0 Type-C to USB 2.0 Type-C cable, in the language guidelines, supports USB 2.0 data and can support USB Power Delivery. It does not carry USB 3.2, USB4, or Alt Mode signals. Pair a USB 3.2 or USB4 host with that cable and the data link falls back to USB 2.0 speed. The guidelines put USB 2.0 Type-C data at up to 480Mbps. Charging can still be a Power Delivery contract on that cable. A slow file copy does not, by itself, prove the power logo is wrong.

Rule of thumb. If fixed voltage is above 20 V on the device’s documentation, prioritize a charger that lists 28V, 36V, or 48V and a USB-C to USB-C cable with the 240W power logo. The pre-3.1 path stopped at 100W on 20V with cables rated at 5A, and Release 2.1 is where USB-IF defined the 240W cable requirements. The USB-C cable guide is the next page once you know which of those two logos you need.

The brick and the cable are both in the power path. A blank housing is not a specification. Read the printed output table and the cable’s power logo.

USB 3.2 and USB4 stay in the data column

The USB 3.2 specification page defines multi-lane operation, up to two lanes of 10Gbps for a 20Gbps transfer rate, and names three transfer rates: 20Gbps, 10Gbps, and 5Gbps. It also says USB Type-C cables were designed from the start to support more than one lane. That sentence is about data lanes. It is not a wattage.

The USB4 page calls USB4 a major update to USB architecture that extends USB Type-C performance, builds on USB 3.2 and USB 2.0, and can run up to 80Gbps over 80Gbps certified cables. It keeps compatibility with USB 3.2, USB 2.0, and Thunderbolt 3, and the link settles at the best speed both ends share. USB-IF’s language guidelines tell makers to advertise data as “supports USB 80Gbps”, “USB 40Gbps”, “USB 20Gbps”, “USB 10Gbps”, or “USB 5Gbps”, and to advertise power with the separate line “supports USB Power Delivery.”

Put those marks in different fields when you shop:

Where the path fails

The third row is the one that used to get filled with sample splits. USB-IF does not publish a universal two-port split. It says each device takes only the power it requires. The allocation for a particular brick is printed by that maker. If the listing has no simultaneous table, you do not yet know what the laptop port keeps when a phone is plugged in beside it.

How to read one charger without borrowing another product’s numbers

Start from the device page, not from the largest number on the brick.

1. Write down the fixed voltage that page asks for. If it is 5V, 9V, 15V, or 20V, you are still inside the voltages USB-IF called previously defined. If it is 28V, 36V, or 48V, you are in the 2021 addition.
2. Find that same voltage on the charger’s output table, with the current printed beside it. Multiply once: power in watts equals that voltage times that current. Compare the product with the device’s stated need. Do not add every voltage row together and call the sum the port’s output.
3. Match the cable logo. The compliance program’s two power labels are 60W and 240W. The 20V at 3A case is the one USB-IF ties to a 60W mark in its 20Gbps example.
4. If more than one port will be live, read the simultaneous table for that charger. Leave the table blank in your notes until you have it.

When a charge stops or a laptop reports a weak adapter, change one part at a time. The USB-C charger troubleshooting guide walks through the adapter, the cable, and the device connection. A magnetic wireless puck is a different charging type. The Qi2 and MagSafe comparison is the page for the puck, the case, and the phone. The wall contract on this page does not set that wireless rate.

The cost of a contract you cannot use

There is no price on this page. The waste is capacity you cannot contract, and the time you spend swapping parts. A charger that lists 28V, 36V, or 48V still cannot deliver that fixed voltage through a cable whose power logo stops at the 60W class when the device page asks for a voltage above 20V. The brick you bought for the higher range then behaves like the older 20V path. A USB4 or USB 3.2 mark on the same cable does not repair that. Data lanes and the power logo answer different questions.

The practical ledger is short. Record the device voltage, the charger row you will use, the cable logo, and whether a second port will be occupied. If any cell is blank, that blank is the gap, not a reason to assume the headline wattage. The Charging and Power guides collect the connector, cable, phone, and wireless pages so the next check stays on this site.

Takeaway: Match one documented voltage row and one cable power logo. Leave every phone peak on the page that printed it.

Sources

Checked 18 October 2026. Figures in the body come from these USB-IF pages and the developer update PDF. The document library lists USB Power Delivery Specification Revision 3.2 Version 1.2, with 09/14/2026 on that library page. The voltage and wattage sentences here are the ones still printed on the public charger page and in the 26 May 2021 announcement. Phone peaks are intentionally not copied here.

• USB-IF: USB Charger (USB Power Delivery)
• USB Promoter Group: USB PD Revision 3.1 developer update, 26 May 2021
• USB-IF: USB Type-C cable and connector language guidelines, file dated 20 March 2023
• USB-IF: USB Type-C Cable and Connector Specification page
• USB-IF: Cables and Connectors
• USB-IF: USB 3.2 Specification
• USB-IF: USB4