Enter your wake-up time. Instantly see if you'll get enough sleep tonight.
| Sleep rating | — |
| vs. recommended minimum | — |
| Deep sleep window | — |
No apps. No accounts. Just answers.
"Can I sleep now?" "How long should I nap?"
One or two inputs. Bedtime, wake-up time, nap length — that's it.
Duration, cycles, rating, and a short tip.
Pick the one that fits your question.
Enter bedtime and wake time. Get actual sleep length, cycle count, and a data-backed rating.
Most UsedHow long until you wake up? See cycles at a glance.
Reverse-engineer your ideal bedtime from 90-min cycles.
PopularPick a nap length and see the best wake time.
Recommended daily sleep by age.
Crossing time zones? Estimate adjustment days.
Track deficit from consecutive short nights.
When your last coffee clears your system.
Evidence-based guides, tool walkthroughs, and the science behind better rest.
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Looking for the best white noise machine for sleep? I tested popular models and share what to consider, plus how to use one with your sleep cycle.
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