About the Sleep Efficiency Calculator
Sleep efficiency: time actually asleep as a percentage of time in bed — 85%+ is considered good.
Also known as: sleep quality percentage, time in bed, sleep efficiency formula, time-in-bed.
How to use this calculator
- Enter minutes asleep, minutes in bed.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Open “Step-by-step” to see how the answer was worked out.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
Sleep efficiency = Minutes asleep ÷ Minutes in bed × 100
Worked example
Using the values pre-filled in the calculator above:
- Minutes asleep = 400
- Minutes in bed = 470
the calculator returns:
- Sleep efficiency: 85.11%
Working
Sleep efficiency = 400 ÷ 470 × 100 = 85.1064%