When you’re on vacation, there are plenty of things to worry about: keeping track of your family’s passports and other documents, arriving on time to bookings/tours, and – most importantly – making sure that everyone is having fun and staying safe.

The last thing you need is to fret about your electronic device.

On the other hand, you likely have a bag full of phones, tablets, and cameras that need charging. Ideally, you want to be able to charge your gadgets at airports and cafes even if you can’t find a free outlet.

A well-chosen power bank is the traveler’s best friend. But there’s a glut of options out there, and it’s hard to know which one to pick. So let’s go over the three most important specs to pay attention to when you’re shopping for a power bank for you and your family.

How to Choose the Right Power Bank for Traveling

Before you invest in a new power bank, here is what you need to consider:

Capacity and Charge

The most important trait to look out for in a power bank is its storage capacity. So the first question you need to ask is which devices are you planning to charge?

Some power banks can even charge your laptop (hell, they can even give your car battery a boost!). But these are often too big to fit in a carry-on bag, which means you can’t take them on flights. The TSA doesn’t allow power banks with lithium batteries in checked bags.

If you absolutely need a laptop-charging power bank, you can find portable and versatile chargers with a capacity of up to 100 Wh. Look for TSA-approved models – here’s a short guide to the rules.

Read more: Which Airline Has the Most Baggage Allowance?

If you need  a power bank with a more serious watt-hour capacity (up to 160 Wh), you can obtain special permission from the TSA. This is typically used for charging medical devices.

Things are much easier if you are happy to look for a power bank for your phone, tablet, camera, or smartwatch. As long as you stay under that 100Wh limit, you can choose any power bank you like.

Anything with a charge (ampere-hour capacity) of up to 5,000 mAh should be small enough to fit in your pocket – an important consideration if you’re traveling light. For family travel, bigger power banks are recommended.

Port Types

Before you invest in a power bank, check the number and type of ports it has.

You’re likely to see at least one USB-A port on every power bank. It functions as an output port, of course, but you also use a USB-A cable to charge the power bank when you’re home or in your hotel room. If you’re expecting to be in a hurry, you might want to pick a power bank with pass-through charging, which means you can charge the power bank and your device at the same time.

For faster charging, many power banks offer a USB-C port as well. Apple device owners should choose a power bank with a Lightning output. Some power banks offer wireless charging as well – in this case, you simply put your phone on top of the battery without having to bother with cables. Make sure your device supports the same kind of wireless charging technology as the power bank you’re planning to buy: Qi is the most common wireless charging standard at the moment.

Cost

Power banks don’t have to be a huge investment. As long as you’re not planning to charge a laptop or other high-capacity device, you can buy a high-quality power bank in the $50-$150 range.

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An Alternative

Again, power banks are great because they’re versatile. You never know when you might need to top off your camera, headphones, or even your tablet.

But if you are only interested in charging your phone, you might want to consider a battery case instead. This device keeps your phone charged all the time and it keeps it well-protected as well. It takes more time to charge your phone this way, but it’s a good option for solo travelers looking for sleek, multifunctional tools.

Quick Overview

The most important things you need to know before you start shopping for a power bank:

  • If you’re flying, stay under 100 Wh. You can take power banks on flights, but only in your carry-on bag.
  • For a pocket-sized power bank, expect a charge of around 5,000 mAh – enough to charge a phone once.
  • For quick charging, look for USB-C ports or a Lightning port (Apple devices only).

Power Banks Will Put Your Mind at Ease

Your phone is a lifeline during emergencies and it’ll keep you from getting lost (especially if you don’t speak the local language). Your tablet or phone can also keep a fidgeting toddler entertained during long journeys, which is a life-saver in its own right. You also want to be able to take the perfect photo at the perfect time without worrying.

All told, you need a power bank to be able to travel worry-free.

But shopping for any kind of device can be discouraging – the top models seem overpriced, but you don’t want to buy a bunk product. It can seem difficult to find a device that is compatible with everything you need.

Don’t get discouraged! Power banks are built to be sturdy, and they should last you a few years even with heavy travel. Do your research now, buy the best power bank for your needs, and then sit back and relax.