Sleep Calculator

Find the perfect bedtime or wake-up time based on 90-minute sleep cycles.

Go to sleep at
Cycles

09:46 PM

9h of sleep

6 cycles

Excellent — 9h sleep

11:16 PM

7h 30m of sleep

5 cycles

Great — 7.5h sleep

12:46 AM

6h of sleep

4 cycles

Good — 6h sleep

02:16 AM

4h 30m of sleep

3 cycles

Fair — 4.5h sleep

03:46 AM

3h of sleep

2 cycles

Poor — 3h sleep

05:16 AM

1h 30m of sleep

1 cycle

Poor — 3h sleep

How it works

Sleep happens in 90-minute cycles. Waking up at the end of a cycle (rather than in the middle) means you'll feel more refreshed. This calculator also adds 14 minutes for the average time to fall asleep.

FAQ

Is Sleep Calculator free to use?

Yes, Sleep Calculator is completely free to use on UtilityCove.

Does Sleep Calculator upload my data?

No. Sleep Calculator runs in your browser, so your input stays on your device.

Can I use Sleep Calculator on mobile?

Yes. Sleep Calculator works on modern mobile and desktop browsers.

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