Recovery
Track your last 7 nights of sleep to calculate accumulated sleep debt with a recovery timeline and quality assessment.
Total Sleep Debt
8 hrs
| Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|
| -1 | -1.5 | -1 | -2 | -2.5 | OK | OK |
Sleep debt accumulates when actual sleep falls below your ideal. Recovery assumes ~1 extra hour of sleep per night above your baseline.
My Sleep Debt
8
hours of debt
Significant Debt
aifithub.io
Contract, discovery endpoints, and developer notes for agent use.
Always available for agents
Tool contract JSON
https://aifithub.io/contracts/sleep-debt-calculator.jsonStable input and output contract for this exact tool.
Human review
People can use the browser page to sense-check outputs and charts, but agents should still execute against the contract and discovery endpoints.
{
"tool": "sleep_debt",
"ideal_sleep": 8,
"actual_sleep": [
7,
6.5,
7,
6,
5.5,
8,
8.5
]
} No. Start with /agent-tools.json, then follow the tool's contract URL. The page UI is for human review, not parameter discovery.
Every tool opens in Quick Start first. Advanced Controls keeps the same scenario, reveals more assumptions or diagnostics, and every tool keeps AI integrations inline below the instructions.
Open it when a human wants to sense-check the output, review the chart, or keep exploring related tools after the calculation finishes.
Sleep debt is the cumulative difference between the sleep you need and the sleep you actually get. If you need 8 hours but average 6.5, you accumulate 10.5 hours of debt per week. Sleep researcher Matthew Walker (author of 'Why We Sleep') describes sleep debt as a biological cost that accrues interest — the longer it persists, the harder it is to recover from. Sleep debt impairs recovery, cognitive function, reaction time, and training performance in measurable ways within 48-72 hours of accumulation.
Partially, but not fully. Research by Depner et al. (2019) published in Current Biology showed that weekend recovery sleep restores some cognitive function but does not reverse the metabolic disruption (insulin sensitivity, cortisol elevation) caused by chronic weekday short sleep. The most effective recovery strategy is adding 1-2 hours per night for 7-10 days rather than a single 12-hour sleep binge. Consistent nightly sleep prevents debt from accumulating in the first place.
Under 2 hours per week is generally manageable for most adults. At 5-10 hours of accumulated debt, research shows measurable impairment in muscle recovery (reduced protein synthesis), reaction time (equivalent to 0.05% BAC), and immune function (50% reduction in natural killer cell activity). Above 10 hours, expect significant performance decline, increased injury risk, and hormonal disruption that can take 1-2 weeks of consistent adequate sleep to reverse.
Yes, substantially. Dattilo et al. (2011) showed chronic sleep restriction reduces growth hormone release by up to 70%, since the majority of GH is secreted during slow-wave sleep. Cortisol increases by 37-45% with inadequate sleep, promoting muscle catabolism. A landmark study by Nedeltcheva et al. (2010) found that 5.5 hours vs 8.5 hours of sleep during a calorie deficit resulted in 60% more muscle loss and 55% less fat loss at the same caloric deficit — the body preferentially burns muscle instead of fat when sleep-deprived.
The National Sleep Foundation recommends 7-9 hours for adults, but research on athletes suggests 8-10 hours produces optimal recovery and performance. A Stanford study by Mah et al. (2011) showed that basketball players who extended sleep to 10 hours per night improved sprint times by 4% and free throw accuracy by 9%. Most strength athletes and endurance athletes perform best with 8-9 hours. Individual needs vary — some genetic variants (DEC2 mutation) allow full recovery in 6 hours, but this affects less than 1% of the population.
Beyond feeling tired, watch for: needing an alarm to wake up (your body isn't completing sleep cycles), falling asleep within 5 minutes of lying down (healthy sleep onset is 10-20 minutes), needing caffeine to function before noon, increased appetite and sugar cravings (ghrelin increases, leptin decreases with sleep loss), mood instability, and declining workout performance despite consistent training. If you can fall asleep during a mid-afternoon meeting, you likely have significant accumulated debt.
Short naps (20-30 minutes) can partially offset acute sleep debt by restoring alertness and reducing cortisol. However, naps do not provide the same quality of slow-wave and REM sleep that nighttime sleep does. A 20-minute nap is equivalent to roughly 30-40% of the recovery value of 20 additional minutes of nighttime sleep. Naps longer than 30 minutes risk sleep inertia (grogginess) and can impair nighttime sleep quality if taken after 3 PM. Use naps as a supplement to adequate nighttime sleep, not a replacement.
Acute sleep debt (one bad night) reduces strength endurance by 5-10% but has minimal effect on 1RM. Chronic sleep debt (3+ nights) reduces 1RM by 5-10%, endurance performance by 10-15%, and coordination/technique quality by 15-20%. Perceived exertion increases — the same workout feels 10-15% harder. Risk of injury increases approximately 1.7x with less than 7 hours of sleep per night, according to a study by Milewski et al. (2014) in adolescent athletes. Time to exhaustion decreases by approximately 11% after 3 nights of restricted sleep.
Yes. All calculations run client-side in your browser. No data leaves your device. No signup required.
Related Resources
Every link here is tied directly to Sleep Debt Calculator. Use the explanation, formula, examples, and benchmarks to pressure-test the calculator output from first principles.
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