Free Science Tools

Free Tools to
Measure & Fix Your Sleep

Every tool here is built on validated sleep science. Use them to understand your data, identify your gaps, and take targeted action — no sign-up required to start.

No sign-up to use
Evidence-based methodology
Mobile-optimized

Available Now

Live Tools
🌙
Free
Bedtime Optimizer
Sleep timing calculator

Enter your wake-up target, sleep goal, and chronotype to get your optimal bedtime, sleep cycle alignment, and a personalized pre-sleep routine window. The most popular tool on SleepMetric.

Optimal bedtime Sleep cycle map Chronotype-adjusted Caffeine cutoff
Use This Tool
📊
Free
Sleep Debt Calculator
Weekly deficit tracker

Log your actual sleep for the past 7 nights and get your cumulative debt score, a nightly breakdown chart, and a personalised recovery timeline based on your deficit level.

Debt score Recovery timeline Nightly breakdown Science-backed actions
Use This Tool
🦉
Free
Sleep Chronotype Quiz
Personalised chronotype report

8 questions that identify whether you're a Lion, Bear, Wolf, or Dolphin. Get your optimal sleep window, peak focus hours, best workout time, and a personalised 4-step protocol for your type.

Chronotype ID Sleep window Focus peak hours 4-step protocol
Take the Quiz
Free
Caffeine Cutoff Calculator
Precision caffeine timing tool

Enter your wake time, bedtime, caffeine source, and sensitivity level. Get your exact last-caffeine time based on the half-life science, plus a visual breakdown of caffeine activity in your system at bedtime.

Exact cutoff time Half-life breakdown Sensitivity-adjusted Day timeline
Use This Tool
🌡️
Free
Sleep Environment Audit
Bedroom score out of 100

Rate your bedroom across 6 evidence-based categories — temperature, light, noise, air quality, bed surface, and wind-down routine. Get a personalised score, ranked priority fix list, and quick wins you can implement tonight.

Score out of 100 6 categories Priority fix list Quick wins
Audit My Bedroom
Free
Wearable Metrics Decoder
HRV, REM, SpO2 & recovery guide

Enter your HRV, resting HR, deep sleep, REM, SpO2, and total sleep. Get plain-English explanations of every metric, a colour-coded range indicator, cross-metric insights, and a personalised tonight action plan.

6 metrics decoded Range indicators Cross-metric insights Action plan
Decode My Metrics

Coming Soon

In Development
✈️
Coming Soon
Jet Lag Recovery Planner
Circadian reset protocol for travellers

Enter your origin, destination, and flight details. Get a personalised day-by-day protocol covering light exposure windows, meal timing, sleep schedule, and melatonin use to reset your circadian rhythm in the shortest time possible.

Day-by-day protocol Light exposure windows Melatonin timing
Notify Me When Live
📊
Coming Soon
Sleep Score Interpreter
What your device score actually means

Enter your Oura Readiness, Whoop Recovery %, or Garmin Body Battery score. Get a plain-English breakdown of what drove your score up or down, what the algorithm is actually measuring, and the one action that would move it most tonight.

Oura / Whoop / Garmin Score breakdown Top improvement action
Notify Me When Live
😴
Coming Soon
Nap Optimizer
Optimal nap window, type, and duration

Enter your wake time, current time, and energy level. Get your scientifically optimal nap window, the right duration for your goal (10 / 20 / 90 min), and the exact cut-off time that won't disrupt your night sleep or cause sleep inertia.

Optimal nap window Duration by goal Night-sleep safe cutoff
Notify Me When Live

Want the full sleep system?

The Deep Sleep Protocol PDF covers everything the tools point to — sleep architecture, environment, timing, and supplementation — in one complete 66-page guide.