How this calculator works
Late caffeine effects are usually felt as “random bad sleep,” but timing plus sensitivity often explain the pattern. This calculator translates that pattern into an estimated weekly debt to guide behavior changes.
It does not diagnose sleep disorders; it provides a planning estimate you can compare before and after routine changes.
How to use it well
- Enter realistic evening caffeine amounts.
- Use your typical bedtime gap from intake.
- Set sensitivity honestly based on your own response.
- Re-run after reducing dose or moving cutoff earlier.
Worked examples
If active caffeine at bedtime remains high, latency and sleep loss estimates rise, increasing weekly debt.
Small schedule changes can reduce debt meaningfully; use the recovery-nights output to plan realistic correction.
Interpretation guide
Focus on trend direction. If weekly debt remains high after habit changes, tighten cutoff time first before stacking more interventions.
Common mistakes
- Underestimating caffeine in mixed drinks.
- Assuming sensitivity is average.
- Changing too many variables at once.
Action checklist
- Track evening intake for 2 weeks.
- Set a consistent cutoff time.
- Compare before/after outputs.
- Adjust gradually and recheck.
FAQ
How often should I update inputs? Monthly is a strong default; update sooner when conditions shift quickly.
Should I plan with optimistic values? Use conservative baseline values first, then compare upside and downside scenarios.