What is sleep debt (sleep deficit)?

Sleep debt (also called sleep deficit) is the gap between how much sleep you aim for and how much you actually get. This calculator estimates the shortfall over the last 7 days using your target sleep and either seven nightly values or a weekly average.

Can you repay sleep debt?

You can usually reduce a short-term sleep debt by adding a small amount of extra sleep for several nights in a row. A realistic approach is to add 30-45 minutes per night and keep a consistent wake time so your schedule stays stable.

Does napping count toward sleep debt?

Naps can help you feel better and improve alertness, but this calculator focuses on overnight sleep because it drives a consistent sleep schedule. If you nap, treat it as a bonus and prioritize getting closer to your target at night.

How much catch-up sleep is too much?

Large catch-up swings can make it harder to fall asleep the next night and can shift your body clock. A common guideline is to cap catch-up to about 2 hours on a given night and focus on steady, smaller increases instead.

Should I use last 7 nights or a weekly average?

Use last 7 nights if your sleep varies day to day, because it shows where the debt came from. Use a weekly average if you only know a rough number or you track total weekly sleep, since it gives a quick estimate with fewer inputs.

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Sleep Debt Plan

Use this sleep debt calculator to estimate how much sleep you're short (sleep deficit) compared with your target over the last 7 days. Enter your target sleep and either your last seven nights (Sun to Sat) or a weekly average. You'll get your total sleep debt in hours and minutes, a minimal fix plan (minutes to add per night), and a two-week stabilization plan to keep bed and wake times consistent. Informational only. Not medical advice.

Sleep Debt Calculator

Calculate your sleep debt (last 7 days).

Estimate your sleep debt (sleep deficit) over the last 7 days and get a simple catch-up plan.

What you'll get

Total sleep debt (7-day shortfall vs your target)
Minimal fix plan (minutes/night and how many nights)
Two-week stabilization plan (bed + wake consistency)

Enter your target sleep and the last 7 nights (or a weekly average) to estimate your sleep debt (sleep deficit) and get a catch-up plan.

Methods & assumptions

This variant focuses on Sleep Debt Plan.

What this sleep debt calculator tells you

Total sleep debt: how much sleep you're short vs your target across the last 7 days (Sun to Sat).
Minimal fix plan: a small, realistic increase to repay debt without wrecking your schedule.
Two-week stabilization plan: simple rules for consistent bed and wake times.

How to interpret your result: sleep debt is a 7-day total. For example, a 6-hour sleep debt is about 50 minutes per night on average (6 hours / 7 nights).

This tool counts only shortfall (sleep deficit). Extra sleep does not cancel out debt.

Daily sleep debt

Debt per day = max(0, target - actual)

Total sleep debt (7 days)

Total = sum(debt per day)

Weekly average mode

Total = max(0, target - average) x 7

Rounding: results are rounded to the nearest 5 minutes.

Plan rules

Minimal fix plan: add 30 minutes per night until debt is reduced (45 minutes/night if debt is over 7 hours). The last night may require less than the full amount.
Weekend cap: max 2 hours on a given night to avoid shifting your body clock.
Two-week stabilization: keep bed and wake time consistent with a 30-minute buffer, and keep weekend shifts under 1 hour.