Discover the exact amount of sleep your body craves in four simple steps.

By Krissy Brady
July 29, 2016

Scoring enough shuteye is a constant battle-from drinking one coffee too many to stressing when you should be snoozing, it's no wonder more of us don't curl up under our desks for a nap-turned-coma. It doesn't help that most of us have no idea how much sleep we should really be getting since the optimal amount varies from person to person. (Psst...We have The Best Foods for Deep Sleep)

Some of the factors that shape how much sleep we need are out of our hands, such as our age and gender, says Niket Sonpal, M.D., assistant professor at Touro College of Osteopathic Medicine in Harlem, New York. But thanks to a few easy steps, you can stay at the top of your game by honing in on the exact amount of sleep your body needs.

Calculate your (approximate) bedtime

The average sleep cycle lasts 90 minutes, with the average person experiencing five sleep cycles per night-or about 7.5 hours of sleep, says Sonpal. Count back 7.5 hours from the time you have to get up in the a.m., and use this bedtime as a jumping off point.

Start a bedtime ritual

As you adjust to your new bedtime, nix the obvious sleep-ruiners from your routine-drinking too much coffee, binge-watching shows in bed, tossing and turning in super toasty bedding-and create a relaxing bedtime ritual that you can look forward to. Practicing good sleep hygiene is paramount in calculating how much sleep you really need, says Sonpal. If you're cracked out on caffeine late at night or overdose on artificial light before bed, your body will be too out of whack to score an accurate estimate. (Related: Your Evening Coffee is Costing You Exactly This Much Sleep)

Ditch the alarm clock

A clear indicator that you're not getting enough sleep is if you use an alarm to drag yourself out of bed in the morning. "Alarm clocks are a good reminder that it's time to wake up, but you should already be waking up 15 to 20 minutes prior to your alarm going off," says Robert Oexman, D.C., director of the Sleep to Live Institute in North Carolina. If that's not the case even with the changes you've been making, try going to bed 15 minutes earlier than you have been, and see if you still need an alarm clock to get up. Gradually adjust your bedtime (say, every week or every 10 days) until you're waking up comfortably sans alarm. On the flipside, if you're waking up way too early, try going to bed 15 minutes later.

Improve your sleep efficiency

By now, you may have the quantity of sleep you need on lockdown, but the quality still needs work. "There's a natural dip in our circadian cycle in the afternoon, but if you're getting enough sleep at night you should be able to ward off the temptation to sleep or lose focus," says Oexman. If this doesn't sound like you (at all), start tracking your sleep with the same sleep efficiency calculator used by the pros to see where you fall short, says Sonpal.

Here's how it works: Take the total number of hours you spent sleeping or trying to sleep (example: 7.5 hours, or 450 minutes), then deduct the amount of time it took to fall asleep (40 minutes) and the time you spent awake during the night (three pee breaks, for a total of 20 minutes). This gives you the actual amount of time you spent asleep (6.5 hours, or 390 minutes). Divide 390 by 450 and your sleep efficiency score is 87 percent.

If you score 85 percent or higher, then it's a solid indication that you've reached your ideal quantity and quality of sleep, says Sonpal. And if not, you'll know the exact areas you need to work on to improve your percentage. Bam.