Best Under-Mattress Sleep Trackers 2026
Contents
Wearable sleep trackers require wearing something to bed -- rings, watches, headbands -- that many people find uncomfortable or forget to charge. Under-mattress trackers solve this: slide a thin pad or sensor strip beneath your mattress once and never think about it again. The device detects heartbeat, breathing, and movement transmitted through the mattress surface using ballistocardiography (BCG), the same physics used in hospital bed sensors.
How Under-Mattress Trackers Work
Ballistocardiography (BCG) measures the tiny recoil forces your body exerts against the mattress with each heartbeat. A pressure-sensitive strip placed under the mattress detects these micro-vibrations and uses algorithms to extract:
- Heart rate and HRV -- from the BCG waveform peak-to-peak intervals
- Respiratory rate -- from the slower oscillation superimposed on the BCG signal
- Movement -- from gross accelerometric detection of position changes
- Sleep stages -- inferred from combinations of HRV, respiratory rate, and movement patterns
Feature Comparison Table
| Model | Sleep Stages | Apnea Screen | HRV | Two-Person | Subscription |
|---|---|---|---|---|---|
| Withings Sleep Analyzer | Yes (4-stage) | Yes (clinically validated) | Yes | 2 sensors | None |
| Emfit QS | Yes (4-stage) | Breathing disturbance | Yes (HRV30) | 2 sensors | Optional cloud |
| Sleepme Dock Pro | Yes | No | Yes | No | Optional |
| Beautyrest Sleeptracker | Yes (4-stage) | No | No | Yes (dual) | None |
| Beddit 3.5 | Basic | No | No | No | None (Apple Health) |
| SleepScore Max | Yes | No | No | No | Premium tier |
| ResMed S+ | Yes | No | No | No | None |
Top 7 Under-Mattress Sleep Trackers
1. Withings Sleep Analyzer
The Withings Sleep Analyzer is the benchmark for under-mattress tracking. Its clinically validated apnea screening (FDA-cleared algorithm) sets it apart from every competitor. The device detects breathing disturbances, logs snoring via microphone, and delivers 4-stage sleep classification (awake/light/deep/REM) with no subscription and no wearable. The accompanying app aggregates sleep scores, trends over weeks, and heart rate curves for each night.
Pros
- FDA-cleared apnea screening
- Snoring detection via built-in mic
- No subscription -- all features free
- 4-stage sleep classification
- Works with Apple Health and Google Fit
Cons
- Single-user per sensor
- Requires Wi-Fi (no Bluetooth-only mode)
- Occasional false positives on apnea screen
2. Emfit QS
The Emfit QS is the choice for biohackers and athletes who want detailed HRV30 (30-second rolling HRV window) data logged throughout the night. Developed in Finland with clinical roots, it exports raw data for analysis in third-party tools. The local data option (no cloud requirement) is a privacy advantage over most competitors. Sleep staging accuracy is on par with Withings.
Pros
- Detailed HRV30 overnight curves
- Raw data export for third-party analysis
- Local mode -- no mandatory cloud
- Compatible with two sensors (couples)
- Strong accuracy on thin innerspring mattresses
Cons
- App design is utilitarian -- not consumer-friendly
- Higher price than Withings
- Optional cloud subscription for full history
3. Beautyrest Sleeptracker
The Beautyrest Sleeptracker is a dual-zone sensor designed from the ground up for two-person tracking. Both zones are logged simultaneously in a single app session, with each sleeper's data displayed side-by-side. The device also integrates with select smart home platforms for automatic sleep-linked adjustments (thermostat, lighting). No subscription required.
Pros
- Dual-zone -- both partners tracked simultaneously
- Single app, side-by-side data view
- Smart home integrations (Nest, Alexa)
- No subscription
- Simple plug-and-play setup
Cons
- No apnea screening
- HRV reporting is basic (no raw data)
- Less granular sleep stage data than Withings
4. Beddit 3.5 (Apple)
Acquired by Apple, the Beddit 3.5 integrates natively with Apple Health, feeding heart rate, respiratory rate, and sleep data directly into the Health ecosystem without a third-party account. For iPhone users already invested in Apple's health tracking, this is the frictionless path. No subscription, no extra app -- just Apple Health.
Pros
- Native Apple Health integration
- No subscription, no third-party account
- Respiratory rate tracking
- Heart rate throughout the night
- Thin, flexible sensor strip
Cons
- Single-user only
- No apnea screening
- Limited app features outside Health app
- Requires iPhone (no Android)
5. SleepScore Max
The SleepScore Max takes a different approach: it sits on the bedside table and uses low-power sonar (radio waves) to detect chest movement through the air, requiring no contact with the mattress or body at all. This makes it ideal for people who don't want anything under the mattress. Accuracy is solid for a non-contact device, though it's more sensitive to sharing a bed with a partner.
Pros
- Completely contactless -- nothing on or under the bed
- Easy setup (bedside unit)
- Respiratory and movement tracking
- Works with any mattress thickness
Cons
- Partner interference in shared beds
- Premium subscription for full history
- No HRV data
- Less accurate sleep staging than BCG sensors
6. Sleepme Dock Pro
The Sleepme Dock Pro (formerly ChiliPad Dock Pro) combines active temperature regulation with sleep tracking -- a unique combination. The mattress pad circulates cooled or warmed water and simultaneously monitors HRV and sleep stages. If you're already investing in a temperature-regulating pad, this adds passive tracking with no separate device required.
Pros
- Active cooling AND tracking in one device
- HRV monitoring
- App-controlled temperature automation by sleep stage
- Works up to 14-inch thick mattresses
Cons
- Very high price point
- Optional subscription for advanced features
- Bulky bedside unit with water reservoir
7. ResMed S+
Made by the world's largest CPAP manufacturer, the ResMed S+ is a non-contact sonar-based sleep tracker positioned for clinical users. It pairs with the ResMed S+ app for sleep coaching and integrates with connected health platforms. Given ResMed's respiratory focus, the breathing rate tracking is particularly well-calibrated.
Pros
- Clinical-grade respiratory tracking
- Built-in sleep coaching (smart alarm, audio content)
- Non-contact -- nothing on the bed
- Made by a respiratory health leader
Cons
- Discontinued in some markets -- check availability
- No HRV data
- Older platform; app updates may be limited
Frequently Asked Questions
Are under-mattress sleep trackers accurate?
Yes -- BCG-based under-mattress devices like the Withings Sleep Analyzer match consumer wrist wearables in sleep stage accuracy (roughly 80% agreement with PSG for light/deep/REM). They avoid the motion artifact problem that affects wrist optical sensors during restless sleep.
Do under-mattress trackers work with any mattress?
Most work with mattresses under 14 inches thick. Very thick memory foam can dampen the BCG signal. Innerspring and latex mattresses give the best signal transmission. Air mattresses and waterbeds are not compatible.
Can under-mattress trackers detect sleep apnea?
The Withings Sleep Analyzer includes a clinically-validated breathing disturbance detection feature that screens for apnea-hypopnea events. This is a screening tool, not a formal diagnosis -- follow up with a sleep physician if results are abnormal.
Do under-mattress trackers work for two people?
Two sensors are needed for two-person tracking. The Withings Sleep Analyzer and Emfit QS can be paired as a set. The Beautyrest Sleeptracker has built-in dual-zone capability.
Is there a monthly fee for under-mattress sleep trackers?
Withings and Beautyrest have no subscription. Emfit QS has an optional cloud tier. SleepScore Max has a premium subscription tier. Beddit requires only Apple Health with no separate subscription.
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