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Buying Guide: The Best Portable Chargers and Power Banks for 2026
What Size Backup Battery Do You Need?
These days, "small" portable batteries have a capacity of around 5,000mAh, which means they easily fit into your pocket and have enough power to fully top up your phone once.
Meanwhile, a 10,000mAh battery can give many of today’s flagship phones about two full charges. A 20,000mAh battery can charge two phones twice or a phone twice and a tablet once. Some power banks have enough juice to power laptops. Of course, a higher capacity often translates to a heavier, larger, and more expensive battery.
Ultimately, it’s best to assess your typical needs before making a purchase. If your phone hits the red zone by mid-afternoon and you only need enough juice to get you to the end of the workday, a 5,000mAh battery should be plenty.
What's the Difference Between Power Input and Output?
Generally speaking, you charge the battery itself via USB-C (input). Speeds differ depending on the battery you choose.
Many batteries still include a standard USB-A port (output). This is for plugging in USB-A-to-Lightning or USB-A-to-USB-C cables for charging your iPhone or Android device. In many cases, the USB-C port used for charging the battery can also serve as an output. This is called Power Delivery. Some batteries include built-in output cables, saving you the trouble of worrying about another wire.
The most important thing is to match the battery’s output to your phone’s input. For example, if you have an iPhone, make sure the battery has a built-in USB-C or Lightning connector, or that it supports the cable you need.
Larger batteries with higher capacities may include multiple ports to support simultaneous input and output. For example, you may see two USB-A or two USB-C ports.
What Is Fast Charging?
Another factor to consider is how quickly a power bank can charge your device. Battery output is measured in voltage and amperage. Amperage (or current) is the amount of electricity that flows from the battery to the connected device, while voltage is the amount of potential energy. Multiplying volts by amps yields wattage, which measures total power. To make devices charge faster, manufacturers either vary the voltage or boost the amperage.
Today’s devices support a wide range of rapid-charging technologies, such as Qualcomm Quick Charge, USB Power Delivery (PD), or proprietary fast-charge systems like OnePlus’ SuperVooc.
Quick Charge works by increasing voltage rather than amperage. This standard typically allows you to charge supported phones to 50% capacity in 5 minutes, which is especially helpful when you need power in a pinch.
Two compatible devices with Power Delivery can negotiate the fastest charging option available based on the charger, cable, and circuitry. It also allows power to flow in both directions.
The most common phones (those in Apple's iPhone and Samsung's Galaxy lineups) support charging rates of up to 45W. It’s best to look for batteries that get as close to your phone’s maximum rate as possible.
Is Pass-Through Charging Safe?
Pass-through charging is another feature to consider; with it, you can charge your device and a portable power bank simultaneously. That's convenient if both your phone and backup battery are running out of power. You shouldn't encounter any safety issues if the manufacturer of the portable battery you buy advertises pass-through charging as a feature; however, the power output to your phone or tablet may be slower in this mode.
How Does Wireless Charging Work?
Wireless charging has become popular because it enables you to power up compatible devices without the need for a cable. Qi is the dominant standard for compatible Android phones (up to 15W), while Apple iPhones rely on MagSafe charging (up to 25W). iPhones will also charge wirelessly on Qi chargers (7.5W) and Qi2 chargers (15W).
Some battery makers have built Qi or MagSafe-compatible wireless charging into the surfaces of their portable batteries. Such batteries mean you can leave the cables at home.
Should You Buy a Battery Case Instead of a Power Bank?
If you often forget to carry your backup battery when you need it most, consider a dedicated battery case instead. These cases combine the portability and protection of a case with extra battery capacity to keep your phone fully charged at all times.
There are several drawbacks. First, they have limited additional capacity. Second, they are limited in terms of the number of phones they support (mostly iPhones, Galaxies, and Pixels). Third, you can't charge much else with them. Stand-alone chargers might also allow you to charge a smartwatch or wireless headphones.
The Best Wireless Chargers
Why fumble around for a charging cable when you can rest your phone on a wireless charging pad? Whether you're an Android user or an iPhone fan, check out our roundups of the best wireless chargers and the best MagSafe chargers to help you cut the cord.