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.
I tried magnesium glycinate for sleep for three months. Here is what changed, what did not, and how to time it with your sleep cycle.
A practical guide to picking blackout curtains that actually block light, based on testing them in a real bedroom with a streetlight outside.
The best room temperature for sleep is usually 65 to 68°F. Here is how I found my own number, and why your thermostat setting is not the same as your bedroom.
Struggling to fall asleep fast? These practical, science-backed tips help you drift off in minutes, not hours.
Eight hours in bed does not always mean eight hours of sleep. Here is why you wake up tired and how to fix it.
Coffee's kick lasts longer than most people think. Here's a realistic timeline based on caffeine half-life, plus how to time your last cup.