Question 1

If I sleep at 10pm when should I wake up?

Accepted Answer

If you sleep at 10pm (adding 15 min sleep latency), ideal wake times using 90-min REM cycles are: 11:45pm (1 cycle), 1:15am (2 cycles), 2:45am (3 cycles), 4:15am (4 cycles), 5:45am (5 cycles — recommended), or 7:15am (6 cycles — optimal for full rest).

Question 2

How do I calculate my wake up time?

Accepted Answer

Enter your bedtime into our sleep calculator. It adds your sleep latency (time to fall asleep, typically 15 min), then calculates wake times at 1.5-hour REM cycle intervals. Choose a time that completes full cycles for the most refreshed awakening.

Question 3

What is the STOP-BANG calculator?

Accepted Answer

The STOP-BANG questionnaire screens for obstructive sleep apnea risk. It asks 8 yes/no questions about Snoring, Tiredness, Observed apnea, blood Pressure, BMI, Age, Neck circumference, and Gender. Score 0–2 = Low risk, 3–4 = Intermediate risk, 5–8 = High risk.

Question 4

What is a 90-minute sleep cycle calculator?

Accepted Answer

Human sleep naturally cycles through NREM and REM stages every ~90 minutes. A 90-minute sleep cycle calculator uses this science to recommend optimal bedtimes or wake times that align with natural cycle completions, so you wake refreshed instead of groggy mid-cycle.

Question 5

How do I calculate sleep efficiency?

Accepted Answer

Sleep efficiency = (Total Sleep Time ÷ Time in Bed) × 100%. A healthy efficiency is 85% or higher. Our sleep efficiency calculator lets you enter your time in bed and actual sleep time to compute your score and get personalized improvement advice.

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