Throughout the night, our brains and bodies pass through four distinct phases of sleep. The length of individual stage varies. Generally, the whole thing lasts around 90 minutes total and goes as follows:

Stage One - the “sort of falling asleep” stage. Maybe you can still hear something but mumble a response or start to twitch. Here, your brain is producing alpha and theta waves as you drift off.

Stage Two - the “short nap” phase. This stage lasts slightly longer, and sleep spindles start appear in your brain.

Stage Three - the “knocked out” stage. Your muscles sink deep into the mattress, slow delta waves form in the brain, and your body repairs tissue and immune health.

Stage Four - REM sleep. This is where weird dreams come to life, and your brain starts to download long-term memories and facilitates learning. Waking up during REM can seriously ruin a good night’s sleep.

Do you have an 8 am meeting and need to get out of bed by 6:30? Most of us know this information already, as we set standard alarms in this situation. However, it’s still an important step for a sleep calculator.

Save the sleep calculator link to your favorites, or visit the App/Google Play store to download the app. From there, each night on your way to bed, work backwards to figure out the ideal time to hit the hay.

Most research recommends 7-9 hours of sleep each night, which comes out to around 5-6 sleep cycles per night. If you really can’t avoid it, shoot for four cycles and six hours of sleep on a tough schedule.

Try and stick to a regular sleep schedule if you can, even on the weekends. Adjusting your bedtime and morning alarm each day can depreciate your mood and energy levels over time. Help your body settle in to a natural circadian rhythm by practicing diligence. If you want to get a few extra hours on Sunday morning, add another cycle and sleep in.