If a charger you can attach to your keys is the name of the game, size is an understandable consideration. If it's too big, it becomes less of a keychain and more of a charger you chain keys to. For a smaller keychain charger, there's the Iniu SnapGo Portable Charger, available on Amazon for $24.99.

This little guy only measures several inches across and weighs around a quarter of a pound. It's got a simple, compact design, including a metal keyring to attach your keys, a front-facing charging pad for smartwatches, and a built-in braided USB-C cable that plugs directly into phones and other compatible devices, like an AirPod charging case. It has a 5,000 mAh, 20W battery that provides enough power to charge an iPhone 17 Pro from 20% to 57% in about 30 minutes. 

Amazon shoppers have given this particular charger a 4.5 out of 5 rating, appreciating its small size and reliable charging efficacy. It's also TSA-approved, and at under $50, it's a clear appeal. The only notable complaint from one user is that it's a little finicky to charge a smartwatch with the cord, requiring a manual power-up after plugging it in.

The best portable chargers are those that can charge multiple kinds of devices simultaneously. You never know what could need a quick bump of power while you're out and about, after all. The Chaligti Portable Charger offers a healthy amount of that extra utility, and it's available on Amazon for $32.99.

This charger features a pair of deployable cords, one USB-C and the other Apple-compatible, plus additional input ports and a smartwatch charging pad on the front, allowing you to plug in and charge multiple devices of different types at the same time. Its current battery capacity is displayed on the frontal LED meter, which also lets you know when power is coming and going. You can clip it to your keys or bag with the aircraft-grade alloy keyring, which attaches to a thick strap.

Both Amazon and its shoppers like this keychain charger, with the former providing an Amazon's Choice badge and the latter bestowing a collective 4.5 out of 5 rating. In addition to its sturdy keyring and charging capability, several users complimented the array of colors the charger comes in, making it a nice complement for bags.

In addition to being small and good at charging, something you would hope to get out of any portable charger, keychain or otherwise, is general charging safety, including protection against over-volting or over-heating, among other worries. If you want a keychain charger that has a little extra in the defense department, there's the Citicr Portable Charger, available on Amazon for $39.99.

Similar to its contemporaries, this charger features built-in Apple and USB-C charging cables, output ports, and a magnetic charging pad for smartwatches. It's also got an alloy keyring and leather strap you can use to attach it to your keys or bag. Where this charger differentiates itself is in its safety features, specifically a six-layer guard framework that protects against overcurrent, overvoltage, short circuits, overheating, overdischarging and battery swelling.

This Amazon's Choice portable charger has garnered a 4.3 out of 5 rating from shoppers, with one user going as far as to call it their all-time favorite charger. They loved the charger's speed and power and its cute design, though they do caution that the built-in cables can become harder to keep in place over time.

If you're not sure exactly what you want from a portable charger, the sensible option would probably be to get a device that packs a little bit of everything. The Rorry CharmGo Portable Charger has most of the same features as the preceding devices, and it's available on Amazon for $29.99.

Through its built-in cables, ports, and charging pad, this charger can simultaneously power Apple and Android devices, smartwatches, and other accessories from its 5,000mAh battery, which is protected against overvoltage, overheating, and short circuits, among other potential issues. It can hang from your keys, bag, or belt loop via its keyring and strap, and it's available in 16 different colors so that you can coordinate it with your personal style.

This device is an exceptionally popular choice, with a 4.4 out of 5 rating from Amazon users, in addition to its Amazon's Choice badge. Users consider it to be a reliable choice, with one user keeping it on hand for the duration of a trip around Las Vegas. Another user cautions, however, that a full power-up of a phone, from 30% to full, can nearly deplete the charger's battery.

While a portable charger aims to provide ample power while remaining portable, depending on your personal use case, you might need a little more capacity and functionality than the average keychain charger can offer. For a heartier option, there's the Rorry Flow Portable Charger, available on Amazon for $42.99.

This keychain charger is a bit beefier than its contemporaries, though it still has a keyring so you can clip it onto your bag or your keys. In exchange for its larger size, it has a hefty 10,000mAh, 40W battery that can charge an iPhone 17 to 50% in just 20 minutes. It has one built-in USB-C charging cable, two output ports for additional devices, and a smartwatch pad on the side. It also has folding prongs you can plug into any standard outlet for a quick charge, for both the charger itself and any devices plugged into it.

This larger, yet still portable charger has a 4.6 out of 5 rating, with one Amazon user calling it a "pint-sized powerhouse" for its fast charging speed and convenient folding plug. Another user offered similar praise, though they wished it had an LED power display like other devices.