Garmin vs Apple Watch sleep scores: why they differ
By Wellhero · Published
You wake up feeling rested. Apple Watch gives the night a high sleep score, while Garmin says it was poor. Both recorded almost nine hours of sleep. How can the results be so far apart?
The watches can disagree about the stages within those hours, and their scores give different importance to different aspects of sleep. Comparing the totals alone hides both differences.
What Apple and Garmin score
Both use a scale from 0 to 100, but a point does not have a shared meaning across the two systems. Each score summarizes the night according to that product's criteria.
| System | What contributes to the score |
|---|---|
| Apple Watch | Time asleep, consistency of bedtime and interruptions during the night. |
| Garmin | Duration and sleep quality, including stage amounts and patterns, awake time, restlessness and average overnight stress derived from HRV. |
Apple's Sleep Score guide lists those three components. REM and deep-sleep proportions are not listed as direct components of the total. The stage chart can therefore tell a different part of the story from the headline score.
Garmin's explanation includes both sleep structure and overnight stress in its assessment of quality. Agreement on duration leaves several other inputs on which the two systems can differ.
Same duration, different sleep stages
In the Reddit discussion that prompted this comparison, one person reported a Garmin score of 50 and an Apple Watch score of 94. Apple recorded 8 hours 49 minutes of sleep; Garmin recorded 8 hours 44 minutes. The person felt good that morning.
The stage breakdowns were much further apart. Apple reported 1 hour 55 minutes of REM, compared with Garmin's 47 minutes. Garmin reported more deep sleep than Apple. Those details show that the devices agreed on the length of the night while describing its contents differently.
Garmin uses heart rate, HRV and movement in its sleep tracking. Apple's sleep-stage validation report explains how its estimates were evaluated against laboratory polysomnography. A watch's stage labels are estimates, so two charts can differ without either showing exactly what happened throughout the night.
The Reddit report illustrates the question; it cannot establish which device was more accurate or whether Garmin systematically scores sleep lower. The reported totals also do not give us enough information to reconstruct either score.
Why a low score can clash with feeling rested
A long, uninterrupted night does not guarantee a high score under every scoring system. Apple's published criteria include recent bedtime consistency. Garmin's include overnight stress. A night can look favorable on one set of criteria and less favorable on another.
Garmin's overnight stress label comes from physiological signals; it is not a report of whether you felt worried while asleep. If that component is poor, open its details before assuming that the score means you were awake or slept too little. Its inclusion is a possible reason for a disagreement, not a diagnosis of what happened in this person's night.
Record how rested you feel alongside the score. Feeling good cannot validate a particular REM estimate, but it adds context when a number seems surprising. Note whether the mismatch repeats and whether the underlying measurements change with it. Several nights recorded in the same way give you more to compare than one morning.
Check whether the night is complete
Before interpreting the scores, compare the recorded start and end times. If one watch missed part of the night, the two apps are summarizing different records. Also check whether you are comparing time asleep with time in bed.
Look for gaps in the stage timeline or overnight measurements. An absent REM record does not establish that you had no REM sleep. Apple's and Garmin's public explanations linked above do not document every rule for incomplete inputs, so there is no reliable universal adjustment you can apply to the total yourself.
If Apple Health shows only Asleep without a stage breakdown, our guide to missing Apple Watch sleep stages explains how to inspect the original entries and their source. Keep those records while investigating the discrepancy.
Which result should you trust?
Start with the part you can check. If you remember being awake until midnight and one device says you fell asleep much earlier, that timing error is more useful to investigate than the difference between two overall scores.
- Compare the same date and sleep interval, including any gaps in recording.
- Open the breakdowns. Find whether the disagreement concerns duration, stages, interruptions or another input.
- Review several nights within each system. Keep a short note of how rested you feel so the score is not your only record.
- If a recording error keeps recurring, save the affected dates and software versions for that device's support team.
A score of 94 is not evidence that a device is more accurate than one showing 50. For tracking changes over time, use a consistent source and look at the details behind an unusual result.
Why Wellhero may show another score
Wellhero analyzes sleep records from Apple Health and provides its own sleep-quality summary. It considers recorded duration, sleep stages, interruptions and heart rate. Because apps interpret the available information differently, Wellhero and Apple's Sleep Score can differ even when they use records from the same watch.
Check the timeline and available measurements alongside the total, especially when some data is missing. The score summarizes the records the app received; it cannot recover measurements the watch did not capture. Recovery is a separate assessment.
The Wellhero sleep-tracking guide shows how to read the quality summary, stage timeline and overnight vitals together.