Calculator
Example data table
| Day | Actual (h) | Goal (h) | Daily deficit (h) |
|---|---|---|---|
| 1 | 7.0 | 8.0 | 1.0 |
| 2 | 6.5 | 8.0 | 1.5 |
| 3 | 8.0 | 8.0 | 0.0 |
| 4 | 5.5 | 8.0 | 2.5 |
| 5 | 7.5 | 8.0 | 0.5 |
| 6 | 6.0 | 8.0 | 2.0 |
| 7 | 8.5 | 8.0 | 0.0 |
This example shows how daily gaps add up to weekly debt.
Formula used
- Effective sleep: effective = actual × (efficiency ÷ 100)
- Daily delta: delta = goal − effective
- Debt update:
- If delta > 0, then debt = debt + delta
- If delta ≤ 0 and credit is enabled, then debt = max(0, debt − min(|delta|, cap))
- Goal met: goal% = (total effective ÷ total needed) × 100
- Recovery days: ceil(debt ÷ daily extra) (with cap applied if enabled)
How to use this calculator
- Set your nightly sleep goal in hours.
- Choose the number of days you want to analyze.
- Optionally adjust efficiency to reflect sleep quality.
- Enter your total sleep hours for each day.
- Press calculate to view totals and the daily breakdown.
- Use CSV or PDF to save and track progress.
FAQs
1) What is a sleep deficit?
It is the gap between your sleep goal and your effective sleep. This tool sums those gaps across days to estimate a running sleep debt.
2) Can one long night erase the whole debt?
Often not. That is why the calculator includes an optional daily credit cap. It limits how much surplus sleep can reduce past debt in one day.
3) What does the efficiency adjustment mean?
It scales your reported hours to estimate “effective” rest. If your sleep felt fragmented, you can lower the percentage for a more conservative estimate.
4) Should I enable catch-up credit?
Enable it if you want extra sleep to repay previous debt. Disable it for a strict view that counts only short nights and ignores recovery nights.
5) What period length should I choose?
Seven days is a helpful snapshot, while 14–30 days shows patterns. If your schedule varies by weekday, a longer window can be clearer.
6) Does this include naps?
Enter naps within your daily total if you want them counted. If you prefer to exclude naps, enter only your main sleep duration.
7) How accurate is the recovery estimate?
It is a simple projection: debt divided by planned extra hours. Real recovery varies, so treat it as a planning aid rather than a guarantee.
8) When should I seek professional advice?
If you have persistent insomnia, loud snoring, daytime sleepiness, or safety concerns, consider speaking with a qualified health professional.