Garmin sleep score explained

Sleep score compresses a whole night into one number between 0 and 100. It is built from how long you slept relative to your age, the balance of your sleep stages, how much you woke or stirred, and how well your body recovered overnight as measured by HRV.

The number is only useful as a trend. One night is noise; a week tells you something.

What it actually measures

Garmin’s advanced sleep tracking uses heart rate, heart rate variability and movement to work out when you fell asleep, when you woke, and how long you spent in light, deep and REM sleep. Your age and baseline physiology are factored in, and on some watches respiration rate and blood oxygen are included. The result is a 0–100 score powered by Firstbeat Analytics.

Value bands

Garmin’s four bands. For context, Garmin’s own user data puts the worldwide average sleep score at around 72, with only about 7% of users averaging “excellent”.

How to improve it — three steps

1. Add time in bed — not supplements — Garmin’s own data makes the point bluntly: users averaging 8–8.5 hours score about 78, while users averaging 4 hours score about 35. Duration dominates.
2. Fix the schedule, not just the total — A consistent bed and wake time beats a fluctuating one. Set a sleep window in Garmin Connect so the watch knows what to measure against.
3. Cut late alcohol and late hard sessions — Both raise overnight heart rate and restlessness, which drags the score down even when you were in bed for eight hours.