What This Calculator Measures
Plan circadian light exposure with morning light, sleep timing, and screen habits.
By combining practical inputs into a structured model, this calculator helps you move from vague estimation to clear planning actions you can execute consistently.
This calculator scores circadian alignment using light, sleep window, and screen timing.
How to Use This Well
- Enter wake time and bedtime.
- Add morning light minutes.
- Set evening screen time.
- Review circadian score.
- Adjust light habits.
Formula Breakdown
Score = 50 + light boost + sleep score - penaltiesWorked Example
- 20 min morning light = +16 pts.
- 60 min screens = -18 pts.
- Score stays in the steady range.
Interpretation Guide
| Range | Meaning | Action |
|---|---|---|
| 80-100 | Strong. | Keep routine. |
| 60-80 | Steady. | Add light minutes. |
| 40-60 | Needs boost. | Reduce screens. |
| <40 | Low. | Reset schedule. |
Optimization Playbook
- Morning walk: add 10-20 minutes.
- Screen curfew: reduce late screens.
- Earlier caffeine cutoff: by mid-afternoon.
- Outdoor breaks: add light spikes.
Scenario Planning
- Baseline: current schedule.
- More light: add 10 minutes.
- Less screen: cut 30 minutes.
- Decision rule: keep score above 65.
Common Mistakes to Avoid
- Skipping morning light.
- Late caffeine intake.
- Long evening screen time.
- Irregular sleep window.
Implementation Checklist
- Set wake time.
- Schedule morning light.
- Set screen cutoff.
- Review weekly score.
Measurement Notes
Treat this calculator as a directional planning instrument. Output quality improves when your inputs are anchored to recent real data instead of one-off assumptions.
Run multiple scenarios, document what changed, and keep the decision tied to trends, not a single result snapshot.
FAQ
How much morning light is ideal?
10-30 minutes helps most people.
Does evening light matter?
Yes, it can delay sleep onset.
What if I work nights?
Adjust light timing to your schedule.