Sleep Debt Calculator

Sleep debt is estimated as the sum of nightly shortfalls: for each night, shortfall = recommended sleep need − actual sleep (floored at zero). We multiply nightly shortfall by the count of nights in the sample to estimate accumulated debt.

Projection combines historical debt with future nightly deficits calculated from a planned average sleep. Repayment calculations divide current debt by extra sleep per night or by a target number of nights to yield nights-to-repay or required extra hours per night.

This calculator follows best-practice software quality and user-safety conventions. Where relevant we reference information-quality and risk-management standards from NIST, ISO, IEEE, and workplace safety guidance from OSHA to inform accuracy caveats and user-facing warnings.

Use the estimate method when you have a representative average and a short history of nights.

Use projection when you want to know how planned sleep behavior will affect debt.

Use repayment plan to explore realistic targets; prioritize gradual increases in nightly sleep (for example 0.25–1 hour) rather than extreme additions.

If recommended_hours = 8, avg_sleep = 6.5 over 7 nights: nightly deficit = 1.5, estimated debt = 1.5 × 7 = 10.5 hours.

If historical debt = 10.5 hours and planned future avg_sleep = 7 for 7 nights: future nightly deficit = 1, projected debt = 10.5 + 1 × 7 = 17.5 hours.