Sleep score explainer

Oura

Sleep Score

85–100 Optimal · 70–84 Good · 60–69 Fair · 0–59 Pay attention. Oura doesn't publish weights, but calls total sleep the most significant contributor. Source: Oura, Sleep Contributors.

• Total sleepTime in light, REM and deep sleep. Oura says most adults need 7–9 hours.
  What changes it: What "good sleep" means, Consistent wake time
• EfficiencyShare of time in bed spent asleep. Oura treats 85% as a sign of uninterrupted sleep.
  What changes it: Caffeine cutoff, Sleep restriction
• RestfulnessWake-ups, excess movement and getting out of bed.
  What changes it: Alcohol, Room temperature, Noise and earplugs
• REM sleepOura calls about 1.5 hours optimal for healthy adults.
  What changes it: Sleep stages and cycles, Alcohol
• Deep sleepOura says adults typically spend 15–20% of sleep in deep sleep, less with age.
  What changes it: Building sleep pressure, Caffeine cutoff, Naps
• LatencyTime to fall asleep. Oura calls 15–20 minutes ideal; under 5 may mean you're overtired.
  What changes it: Building sleep pressure, Caffeine cutoff, Wind-down routine
• TimingWhen you sleep. Oura looks for the middle of your sleep between midnight and 3 a.m.
  What changes it: Morning light, Chronotype, Social jet lag

Readiness Score

Same bands as the Sleep Score. Not published. Balance contributors use about two weeks of data, weighted toward the last few days. Source: Oura, Readiness Contributors.

• Resting heart rateLast night's lowest heart rate compared with your long-term average. Oura says late meals, caffeine, alcohol or late exercise can raise it.
  What changes it: Alcohol, Late meals, Exercise timing
• HRV balanceYour recent (about 14-day) HRV compared with your average over about 3 months.
  What changes it: HRV, resting heart rate and temperature, Alcohol
• Body temperatureYour body temperature compared with your usual range.
  What changes it: HRV, resting heart rate and temperature
• Recovery indexBased on your overnight heart rate. Oura's page explains how it's calculated.
  What changes it: Late meals, Alcohol
• SleepLast night's Sleep Score.
  What changes it: What "good sleep" means
• Sleep balanceYour sleep over the past two weeks.
  What changes it: Consistent wake time
• Sleep regularityHow consistent your bed and wake times were over the previous two weeks.
  What changes it: Consistent wake time, Social jet lag
• Previous day activityYesterday's activity.
  What changes it: Exercise timing
• Activity balanceYour activity over about 14 days compared with about 2 months.
  What changes it: Exercise timing

Apple Watch

Sleep Score

96+ Very high · 81–95 High · 61–80 OK · 41–60 Low · 0–40 Very low. Apple publishes the split: 50 points duration, 30 bedtime consistency, 20 interruptions. Source: Apple, View your Sleep Score on Apple Watch.

• Duration (50 points)How long you slept.
  What changes it: What "good sleep" means, Bedtime calculator
• Bedtime consistency (30 points)When you fell asleep over the last 13 nights.
  What changes it: Consistent wake time, Social jet lag
• Interruptions (20 points)How often you woke and how long you stayed awake.
  What changes it: Alcohol, Noise and earplugs, Room temperature

Garmin

Sleep Score

90–100 Excellent · 80–89 Good · 60–79 Fair · below 60 Poor. Garmin doesn't publish weights. It estimates stages from heart rate, HRV and movement. Source: Garmin, How Garmin Watches Track Your Sleep and Calculate Your Sleep Score.

• DurationHow long you slept.
  What changes it: What "good sleep" means, Consistent wake time
• Sleep stagesTime in light, deep and REM sleep, and transitions between them.
  What changes it: Sleep stages and cycles, Caffeine cutoff
• Awake time and restlessnessTime awake and restless during the night.
  What changes it: Alcohol, Room temperature
• Stress during sleepGarmin's stress measure while you sleep.
  What changes it: Alcohol, Exercise timing, HRV, resting heart rate and temperature

WHOOP

WHOOP's help pages about its sleep score couldn't be loaded when we checked, so we only list what its developer documentation confirms: what goes into Recovery.

Recovery

67–100% green · 34–66% yellow · 0–33% red. Not published. Source: WHOOP, WHOOP 101.

• Heart rate variability (RMSSD)WHOOP reports it as RMSSD, in milliseconds.
  What changes it: HRV, resting heart rate and temperature, Alcohol
• Resting heart rateYour resting heart rate.
  What changes it: Late meals, Exercise timing
• Respiratory rateBreaths per minute.
  What changes it: HRV, resting heart rate and temperature
• SleepHow much and how well you slept.
  What changes it: What "good sleep" means
• Skin temperature and blood oxygenOn devices that measure them.
  What changes it: HRV, resting heart rate and temperature