Before you buy Garmin Index Sleep Monitor
A sleep-only armband, compared with a tracker you wear day and night.
Garmin Index Sleep Monitor is a $169.99 band worn on your upper arm, only at night. It focuses on sleep, keeps both wrists free and lasts up to seven nights per charge. Ray is worn on the wrist around the clock and tracks your day as well as your sleep, including steps and light exposure.
The short answer
Choose the Index Sleep Monitor if you only want overnight data and already use Garmin Connect. Choose Ray if you want one tracker for day and night that you never charge.
Garmin Index Sleep Monitor status: Currently sold.
Side by side
Specs are manufacturer claims and US pricing snapshots, not lab-test results. A blank promise is less useful than a clear tradeoff, so we keep this list deliberately practical.
| What changes | Chargerless Ray | Garmin Index Sleep Monitor |
|---|---|---|
| Format | Screen-free wristband | Sleep-only upper-arm band |
| Power | Light powered; no charging routine | Rechargeable; up to 7 nights |
| Screen | None | None |
| US price | $219 silver / $249 gold | $169.99 |
| Required subscription | None | None |
| Core tracking | Sleep, heart rate, HRV, temperature, steps and light exposure | Sleep, HRV, respiration, Pulse Ox and skin temperature |
Still weighing fitness trackers? Read what to look for in a tracker you'll want to wear every day.
Neither wins every category
The best tracker is the one whose compromises fit your life—and that you will actually keep wearing.
Why choose Ray
Ray tracks day and night, including steps and light exposure, from the wrist.
Why choose Garmin Index Sleep Monitor
Index Sleep Monitor keeps both wrists free and focuses tightly on sleep.
Research note. Competitor facts were checked against Garmin Index Sleep Monitor product comparison on August 20, 2026. Prices, promotions, regional features and announced-product timelines can change. Ray details reflect the current Chargerless product page. Neither product is a substitute for medical care.
Wear your health. Not a charger. Ray tracks the essentials in a 7-gram bracelet powered by light. Silver starts at $219. Gold starts at $249. No required subscription.
See Ray options Browse all 38 comparisons