Our story

About SleepDebtCalc

We build the simplest, fastest, most science-grounded sleep tools on the internet — and we make them completely free.

Our mission

Sleep is the single most under-utilized health, performance, and longevity lever available to human beings — and most of the advice on the internet is either fragmented across a hundred articles or locked behind a $99 wearable. We believe everyone should be able to measure their sleep debt, understand their sleep cycles, and design a recovery plan in under 60 seconds, on any device, without signing up for anything.

SleepDebtCalc exists to translate the best of modern sleep science — the work of researchers like Matthew Walker, Andrew Huberman, and the clinical guidelines of the American Academy of Sleep Medicine — into instant, interactive calculators that answer real questions: How much sleep do I owe? What time should I go to bed? Is my caffeine sabotaging my deep sleep?

Always free

All 14 calculators, forever. No paywalls, no signup, no upsell.

No data collection

Your sleep data never leaves your browser. We don't store it.

Evidence-first

Every formula is sourced from peer-reviewed sleep research.

Editorial process

Every article and every calculator on SleepDebtCalc goes through a four-step editorial process before publishing:

  1. Source review. We start from primary sleep research published in peer-reviewed journals such as Sleep, Sleep Medicine Reviews, and Journal of Clinical Sleep Medicine, supplemented by guidelines from major sleep medicine bodies.
  2. Algorithm design. Calculator math is built from documented formulas (caffeine half-life pharmacokinetics, 90-minute cycle architecture, sleep efficiency ratios) and stress-tested against published case studies.
  3. Plain-language writing. Articles are written in everyday language, then reviewed for accuracy and reading level.
  4. Continuous updates. Posts are revisited at least once per year and updated when new research changes the consensus.

What's inside the toolkit

Built on research

Every claim is traceable to a peer-reviewed source or major medical body.

Privacy-first

All calculators run client-side. We never store your sleep inputs.

Built for everyone

Knowledge workers, parents, athletes, students, shift workers, and travelers.

How we stay free

SleepDebtCalc is supported by tasteful, non-intrusive display advertising (including Google AdSense) and the occasional affiliate relationship with sleep-related products we have personally vetted. We never let advertising influence our editorial guidance, and our calculators will always be free, no-signup, and ad-light. See our Privacy Policy and Disclaimer for details.

Get in touch

Questions, corrections, partnership ideas, or research suggestions are always welcome. Visit our contact page or email hello@sleepdebtcalc.com. For terms of use see our Terms & Conditions.

The information on this site is educational and not a substitute for medical advice. If chronic fatigue persists despite good sleep hygiene, please consult a sleep specialist. Read the full Disclaimer.