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01Will your laptop charger work? Check in two taps
You can use your laptop charger for your phone if it ends in USB-C, and it's completely safe. Barrel-plug and magnetic laptop chargers are a different story. Answer two questions to see where yours lands.
Plug it in. It's safe and fast
Use a USB-C to USB-C cable. The charger offers its power levels, your phone picks what it can handle, and you'll usually get full fast-charging speed.
Shop USB-C cablesYes, with a USB-C to Lightning cable
A USB-C laptop charger plus a USB-C to Lightning cable fast-charges iPhone 8 through iPhone 14. Avoid USB-A adapters in between; they drop you to slow speeds.
Shop Lightning cablesThis charger can't charge your phone
Barrel and proprietary laptop chargers don't speak USB, and there's no safe adapter for a phone. Plug the phone into the laptop's USB port instead, or carry a small USB-C charger.
Shop USB-C chargersFine for a top-up, not a fast charge
Laptop USB ports usually supply a few watts. Expect a slow trickle, and none at all once the laptop sleeps on some models. A USB-C port on the laptop may do better.
Shop wall chargers02Why a 65W or 100W USB-C charger won't fry a phone
USB-C laptop chargers use USB Power Delivery, the same standard as phone chargers. They start every connection at 5 volts and only step up when the device asks. Your laptop asks for 20V. Your phone typically asks for 9V. Same brick, different answers.
- Starting voltage
- 5V, before any negotiation
- Common PD levels
- 5V, 9V, 15V, 20V
- Who decides
- The phone
- Typical phone draw
- About 20W to 60W, model dependent
- What a bigger charger adds
- Headroom, not speed
Apple even lists its Mac USB-C power adapters among the chargers you can use with USB-C iPhones. We cover the general rule in using a higher-watt charger.
Many laptop chargers support PD but not PPS. Your Galaxy will still charge, just at regular fast charging rather than Super Fast. Look for "PPS" in the output specs printed on the brick.
03Laptop chargers that won't work
| Laptop charger type | Charges a phone? | Why |
|---|---|---|
| USB-C plug | Yes | Negotiates power with any USB-C device |
| USB-C charger with a removable cable | Yes | Use the cable it came with or any USB-C cable |
| Round barrel pin | No | Fixed voltage, usually around 19-20V, no negotiation |
| Apple MagSafe (Mac) or Surface Connect | No | Proprietary magnetic connectors with no phone end |
| Older chargers with USB-A port on the brick | Usually, slowly | That port is a basic 5V output |
Some Mac chargers have a magnetic cable on one end and a USB-C port on the brick itself. Swap that cable for a USB-C to USB-C one and the brick charges your phone fine.
04Charging from the laptop's USB port
Plugging your phone into the computer itself is safe, but it's the slow option. Older USB-A ports were designed to supply only a few watts, and many laptops cut power to their ports when they sleep.
- USB-A port: a slow trickle. Fine at your desk, not before you head out.
- USB-C port on the laptop: often faster, sometimes close to a small wall charger, depending on the laptop.
- Running on battery: charging your phone drains the laptop. Plug the laptop in first if you can.
- "Trust this computer?" prompts on iPhone are about data, not power. Tap Don't Trust if you just want a charge on a shared machine.
If the trickle is too slow, our slow-charging guide shows where the watts go missing.
05Heat and battery health
+Fine
- A USB-C laptop charger for daily phone charging
- Leaving the phone on it overnight
- Sharing one brick between laptop and phone
–Worth avoiding
- Charging under a pillow or in direct sun
- Gaming on the phone while it fast-charges
- Any charger that's damaged, buzzing or too hot to hold
A phone on a laptop charger runs no hotter than on a phone-sized one at the same speed. Heat comes from how fast the phone is charging and where it's sitting. See phone overheating while charging if yours gets uncomfortably warm.
06One brick for laptop and phone
If you're already carrying a USB-C laptop charger, a second port is the easy upgrade. A two- or three-port GaN charger runs both at once without a second brick in your bag. Size it with the wattage calculator.
Multi-port GaN chargers and a 240W-rated USB-C cable. Check each listing's per-port output.
Questions people ask
Can I charge my iPhone with my MacBook charger?
Yes, if it's a USB-C Mac power adapter. Use a USB-C to USB-C cable for iPhone 15 and later, or USB-C to Lightning for older models. The iPhone takes only what it needs.
Will a 100W laptop charger damage my phone?
No, as long as it's a USB-C PD charger. It starts at 5V and only raises the voltage if the phone requests it. The 100W rating is a maximum, not what it forces out.
Is charging my phone from my laptop bad for it?
No. It's just slow, especially from older USB-A ports. It will drain the laptop's battery if the laptop isn't plugged in.
Can I use a Dell or HP laptop charger for my phone?
Only if it has a USB-C plug. Many newer Dell, HP and Lenovo chargers do. Older ones with a round barrel pin don't speak USB and shouldn't be adapted for a phone.