Reviewed October 2, 2026
Start with your morning
Target bedtime = wake-up time minus desired sleep duration. Preferred dinner cutoff = target bedtime minus three hours. Minimum buffer cutoff = target bedtime minus two hours.
This assumes you fall asleep near your target bedtime. It does not account for sleep latency, awakenings, daylight-saving transitions, or individual sleep needs. The calculator uses clock minutes, without browser date parsing.
Meal Timing Score
We show a score only when you enter a planned dinner time. Dinner is placed between the previous wake period and your selected wake-up. A dinner after target bedtime produces a negative gap.
| Dinner-to-bed gap | Score |
|---|---|
| 180 minutes or more | 100 |
| 120–179 minutes | 70–99 |
| 60–119 minutes | 40–69 |
| 1–59 minutes | 10–39 |
| At or after bedtime | 10 |
Scores interpolate linearly within each range and round to the nearest whole number. This is a transparent product heuristic, not a validated medical measure or a prediction of sleep quality.
Why three hours?
NHLBI advises avoiding heavy meals close to bedtime without prescribing an exact universal cutoff. Our three-hour preference is a planning convention; the two-hour marker is not a medical safety threshold. GERD advice is more specific and applies to people with relevant symptoms.
Sources: NHLBI: Healthy Sleep Habits · NIDDK: Diet and GERD
For reflux, diabetes, pregnancy-related symptoms, eating disorders, shift work, or a prescribed eating schedule, seek individualized guidance.