Not all charging is equal. If your smartphone (or tablet) is low on battery and you only have a limited amount of time to charge it, here’s how you can get the most juice possible.

These tips should work for practically anything that charges via USB, including cameras, peripherals, and any other device you might have.

Don’t Charge From Your Computer’s USB Ports

You can connect smartphones and tablets to your computer via a USB cable and they’ll charge. But they won’t charge as fast as they would if you plugged them into a proper, dedicated charger. In the USB 1.0 and 2.0 specifications, a standard USB port is capable of delivering up to 0.5A. USB 3.0 increases this to 0.9A on typical ports, while a dedicated charging port can offer up to 1.5A. USB 3.1, which is intertwined with (but not the same as) the new USB Type-C standard, supports up to 3A.

For example, Apple’s iPhone 6 ships with a charger that offers up to 1A. If you’re charging an iPhone 6 from a typical USB 3.0 port, you’re only getting 0.9A. if you’re charging it from an older USB 2.0 port, you’re only getting 0.5A. Modern Android phones and other devices will likely be capable of taking more power than a typical computer’s USB ports can provide, too — check your phone or tablet’s specifications to see what it’s capable of drawing. Skip your computer’s USB port and plug your phone or tablet into a dedicated charger.

A high-power USB port on a recent computer may be good enough depending on your device, but it’s better to rely on a dedicated charger if you’re in a hurry.

Use a More Powerful Charger

Rather than simply using the charger that came with your device, you can sometimes charge it faster by upgrading to a more powerful charger. For example, Apple’s iPhone 6 phones ship with a 1A (5W) charger, but they can charge faster when plugged into Apple’s 2.1A (12W) iPad charger. If you want to charge your iPhone 6 faster, plug it into an iPad charger instead of its normal charger.