Best Under-Mattress Sleep Tracker / Sleep Mat (2026) | Withings, OZI, Emfit
Dovy Paukstys
Founder, Komori Care
Best Under-Mattress Sleep Tracker / Sleep Mat
People searching "best under mattress sleep tracker" or "sleep mat" want a pad between mattress and foundation — nothing on the wrist, nothing pointed at the bed. That shelf is real and mature. It is also not the same job as bedside radar.
Disclosure: I am Dovy, founder of Komori Care (bedside radar, coming 2027, wellness only — not a sleep mat). Where mats win, I will say so.
Quick answer
Best under-mattress sleep tracker — pick by job:
- Best overall sleep mat you can buy now: Withings Sleep Analyzer — under mattress, ~$130–$200 class, usually no subscription; duration, stages, HR, breathing, snoring trends.
- Best mat alternatives often named: OZI Sleep Tracker; Beautyrest Sleeptracker-AI / Tempur-class dual mats for mattress-ecosystem buyers.
- Best if you want raw athlete-style HRV from a mat: Emfit QS — higher price, quantified-self framing.
- Best if temperature + cover is the real product: Eight Sleep Pod — not a thin mat; smart cover / thermal lane.
- Skip the mat if your job is sleep position through blankets: Bedside radar (Sleepal sooner; Komori 2027) — see Withings vs radar.
What a sleep mat is good at
Under-mattress sensors feel mechanical forces through the mattress (ballistocardiography / force sensing). Strengths: nothing to wear, nothing to charge on your body, familiar app ecosystems, strong "stages + HR" story for one cooperative sleeper.
Limits that matter:
- Sleep position (back / side / stomach) is usually weak or absent.
- Two people on one mattress create crosstalk — see couples.
- You must install and live with a pad under the mattress.
Mat vs bedside radar vs wearable
| Job | Better form factor |
|---|---|
| Stages / HR tonight, under $200 | Under-mattress mat (Withings) |
| Dual-zone temperature | Eight Sleep cover |
| Individual HRV / readiness | Wearable (Oura etc.) |
| Position through blankets, no camera | Bedside radar |
| Refuse any bed install | Radar or wearable — not a mat |
Where Komori fits
Komori is not an under-mattress product. Design intent is above-bed 60GHz radar for position Night Review, coming 2027, general wellness, not FDA-cleared, not seizure detection (disclaimer). If a mat already answers your question, buy the mat.
FAQ / Quick Answers
- Best under mattress sleep tracker 2026? Withings Sleep Analyzer for most buy-now shoppers.
- Best under mattress sleep tracker without subscription? Withings Sleep Analyzer — one-time purchase around $130–200, no monthly fees, full features unlocked. For full subscription-free comparison across all form factors, see best sleep tracker without subscription.
- Best sleep mat for couples? Dual-sensor Sleeptracker-AI / Beautyrest class — or accept crosstalk on a single Withings strip.
- Sleep mat vs radar? Mats = pressure through mattress; radar = geometry through air/blankets (radar guide).
- Under mattress sleep tracker vs bedside radar — which is better for sleep position? Bedside radar wins for position (back/side/stomach through blankets); under-mattress mats win for stages/HR but usually weak on true orientation classification. See privacy bedside vs under-sheet.
- Is Komori a sleep mat? No — bedside radar, coming 2027.
CTA
Need a mat this week → Withings (or OZI / Sleeptracker-AI). Need position-first contactless without a pad → Komori waitlist for 2027, or get the $49 Insider Pass to lock in founder pricing.
Komori Care is a contactless sleep monitor in development — radar + ambient + on-device audio, no wearable, no camera. Kickstarter launching Q1 2027. Join the waitlist to get notified when we ship.
Keep reading
- Best sleep tracker without subscription — one-time purchase options across all form factors
- Withings vs radar — under-mattress or above.
- Best radar sleep monitor — Kardian, Sleepal, Komori pick-by-job.
- Best sleep tracker without a wearable — mats, beds, bedside radar.
- Best non-wearable sleep tracker — yearless exact-query companion.
- Contactless monitors compared — full field guide.
You can choose a position at lights-out. Knowing what you held until morning is the hard part.
Komori is a contactless monitor that logs which position you slept in, through blankets, with no camera and nothing to wear. Pre-launch — join the list and we'll tell you when it ships.
Keep reading
Want to see your sleep position data?
Join the free waitlist for launch updates. Or lock in founder pricing with the Insider Pass ($49, credited toward your purchase).