Sleep calculators

From wake time, map morning light, caffeine cutoff, meal timing, temperature drop, and target bedtime — the Dusk pillars in one pass.

Wake, typical bedtime, and cups of coffee — latest safe caffeine time from meta-analytic timing data, aligned with the stimulation pillar.

Last seven nights against your target sleep need: cumulative debt, surplus, and a simple read on whether you are trending toward recovery.

Compare weekday and weekend sleep midpoints to estimate social jet lag in hours, with plain-language context from large chronotype studies.

Target bedtime → approximate phase-response window before estimated DLMO, plus why 0.3–0.5 mg matches physiology better than store doses.

Fixed alarm time? Get lights-out options on 90-minute multiples so you are more likely to wake between cycles, not in deep sleep.

Short questionnaire on free-day sleep, alertness, and hunger peaks — mapped to a morning–intermediate–evening read and ideal window hints.

Current time, last wake, and tonight’s bed — whether to nap, 10–20 vs 90 minutes, and latest safe end so night pressure stays intact.

Target bedtime → last-calories cutoff (~3 h) and how that pairs with a tighter daytime eating window for sleep-friendly timing.

Direction and zones crossed → pre-travel shifts, destination morning vs evening light, and nap rules aligned with circadian travel science.

Standard drinks, last sip time, and target bed — conservative buffer before sleep is less likely to shred REM and fragment the second half.

Target bedtime → when to cut bright screens, go warm/dim only, and power down before lights out.

Time in bed and estimated sleep time → efficiency percent, awake-in-bed hours, and whether the pattern looks like restriction or fragmentation.