Sleep Debt Calculator
Sleep debt is the difference between the sleep you need and the sleep you actually get. This calculator tracks your nightly sleep over the past week and shows your total accumulated debt, helping you understand why you may feel fatigued.
Enter your details
Hours slept each night
Your Sleep Debt
ExampleExample figures, not your own. Worked for an adult sleeping 7, 6.5, 7, 6, 5.5, 8 and 8 hours across the week. Enter your own details and press Calculate.
Total Sleep Debt (7 days)
8.0hours
Significant debt - prioritise sleep to avoid health impacts
Average Nightly Sleep
6.9hours
Recommended: 8 hours| Day | Slept | Debt |
|---|---|---|
| Monday | 7.0h | -1.0h |
| Tuesday | 6.5h | -1.5h |
| Wednesday | 7.0h | -1.0h |
| Thursday | 6.0h | -2.0h |
| Friday | 5.5h | -2.5h |
| Saturday | 8.0h | 0h |
| Sunday | 8.0h | 0h |
How It Works
The calculator compares your actual sleep each night against the recommended amount for your age group. Adults aged 18-64 need 7-9 hours per night; over 65 need 7-8 hours. Your sleep debt is the sum of all shortfalls over seven days. Research shows that even modest nightly shortfalls, losing just 30 minutes per night, add up to a significant debt that impairs concentration, mood, and metabolism.
How to use it
- 1Select your age group to set your recommended sleep target
- 2Enter the hours of sleep you got each night for the past 7 days
- 3Click "Calculate" to see your total sleep debt
- 4Review the daily breakdown to identify patterns
- 5Use the recovery suggestions to plan catch-up sleep
Quick Reference
| Weekly Sleep Debt | Severity | Impact |
|---|---|---|
| 0-2 hours | None | Well-rested, optimal performance |
| 3-5 hours | Mild | Slightly reduced focus and energy |
| 5-7 hours | Moderate | Noticeable fatigue, slower reactions |
| 7-10 hours | Significant | Impaired memory, mood changes |
| 10-14 hours | Severe | Increased appetite, weakened immunity |
| 14+ hours | Chronic | Comparable to 1-2 nights of no sleep |
Based on cumulative deficit relative to age-appropriate recommended sleep.
How This Is Calculated
- recommended
- = recommended hours per night for your age group
- actual
- = actual hours slept each night
Sleep debt only accumulates from deficit nights. Sleeping extra on one night does not directly offset a previous deficit in this model, though recovery sleep does help.