A device that measures your sleep hours is called a sleep tracker. Sleep trackers can provide a fascinating insight into the mysterious third of your life you spend asleep.
It might not be as accurate as a professional assessment, but a sleep tracker can give you useful information about the quality of your sleep, and then help you take steps to improve it.
Sleep is a vital part of a healthy lifestyle. Getting enough quality sleep makes you more productive at work, and gives you the energy to exercise; studies have even linked poor sleep with overeating.
Unfortunately, while you can force yourself to go for a run or eat a salad, you can't force yourself to sleep soundly. But there are steps you can take to improve your sleep, and buying a sleep tracker is one of them. These devices may not directly send you off to the land of Nod, but they'll help you work out what makes you sleep better – whether that's ditching the afternoon coffee or going to bed at the same time every night.
Here's our guide to what sleep trackers can do for you, along with a roundup of the best trackers on the market.
How to choose the best sleep tracker for you
Ask yourself first of all what sort of tracker you're looking for. If you're comfortable sleeping with something on your wrist then you can get an excellent watch-style wearable that also doubles as an everyday activity and sports tracker.
Alternatively, you can opt for a tracker that goes next to your bed, or sits under the mattress. Naturally, these devices will only monitor your sleep, but you can expect them to do a terrific job at that.
There are also plenty of sleep-tracking smartphone apps to consider. These aren't quite as accurate as dedicated devices, but they might be more convenient, and are almost always cheaper.
What key features should I look for?
The most basic sleep trackers just record how long you've been asleep for, which is frankly not enough information to be useful. As a minimum, you want to see your sleep broken down into periods of light and deep sleep, along with any times when you were awake. Some trackers can also provide a graph of your movement overnight, and give information on conditions in your bedroom, such as how hot, humid or noisy it is.
If your tracker awards sleep-quality scores, that can make it easy to compare one night with another, and to see how your sleep patterns match up to those of other people in a similar demographic. The goal, of course, is to find what helps you sleep: for example, if you sleep better after exercise, or worse after drinking alcohol, the data from your tracker can help you spot that, and take steps to improve your habits.
Another worthwhile feature is a smart morning alarm that wakes you up at the right point in your sleep cycle so you don't feel groggy. A long battery life is very desirable too: having to charge a tracker every day is a pain.
What else do I want it to track?
Many sleep trackers come built into general-purpose sports watches, which also track everyday activity statistics such as steps and calories burned. Some even feature outdoor sports tracking via GPS. If you're the active type, such designs are well worth a look.
All-day heart-rate tracking is worth considering too, as this can help you keep tabs on your resting pulse rate – a great indicator of your cardiovascular fitness. And if you use one tracker for both sleep and sports, the partner app can pull all that information together to build up a revealing picture of your overall health.