Fine at 11. Kicking the covers off at 3. Pulling them back on by 5. CircadiaOS moves your bedroom through four temperatures every night, on the smart thermostat you already own. No new bed. No cooling pad.
iPhone app. Wellness product, not a medical device.
A thermostat holds whatever you set before bed until morning. Your nights don't work that way.
The room feels right. You pick a number and hope it holds.
Same setting, different night. You lie there hot, doing thermostat math.
You turned it down at 3. Now you're reaching for the blanket you kicked off.
Tell the app when you go to bed and when you get up. Each evening it sends your thermostat a four-phase schedule timed to your night, and it does it again tomorrow.
Example night: asleep 11:00 pm, up 7:00 am
These are starting points, not targets. Run hot? Tap the whole curve cooler, one degree at a time, down to 63°F. The shape stays the same, so the room still eases up before you wake. The peri/post starting curve is on Premium and is covered in the FAQ below.
Nights change from week to week. So the curve isn't fixed, and you're never locked out of it.
Cooling beds and mattress pads work on the bed. CircadiaOS works on the room, with the thermostat that's already on your wall.
| CircadiaOS | Cooling bed (e.g. Eight Sleep) | Water pad (e.g. Sleepme) | |
|---|---|---|---|
| What you buy | Nothing. An iPhone app. | Mattress cover and hub | Pad and water unit |
| Upfront cost | $0 | From $1,999 (one side of the bed), plus a required first-year plan | From $719 |
| What it changes | The whole room, four times a night | The bed surface | The bed surface |
| Ongoing | $12.99/mo or $99.99/yr for Premium. Free plan available. | From $17/mo or $199/yr plan, required for the first 12 months | Distilled water, cleaning |
Prices from Eight Sleep's Pod 6 launch (September 23, 2026) and sleep.me (Chilipad Cube), checked September 2026. Prices change. Trademarks belong to their owners.
Some background from published research. This describes the experience many people have. It is not a claim about what CircadiaOS does for any symptom.
Up to 75% of women have hot flashes around menopause. In the long-running SWAN study, frequent symptoms lasted a median of 7.4 years.
Shifren & Gass, Menopause, 2014 (NAMS). Avis et al., JAMA Internal Medicine, 2015.In a CDC survey of women aged 40 to 59, 56% of perimenopausal women slept under seven hours, and about 36% of postmenopausal women had trouble staying asleep four or more times a week.
CDC NCHS Data Brief No. 286, 2017.In a lab study, women with hot flashes had almost no gap between the body temperature that triggers sweating and the one that triggers shivering. Women without hot flashes had a small buffer. Small changes in temperature matter more.
Freedman & Krell, American Journal of Obstetrics and Gynecology, 1999.In another lab study, hot flashes disrupted sleep mainly in the first half of the night. In the second half, REM sleep appeared to suppress them. The night isn't the same from start to finish.
Freedman & Roehrs, Menopause, 2006.ecobee · Honeywell Home · Sensi · SmartThings-connected thermostats · Nest through Apple Home
Check your thermostatApple Watch · Oura Ring · Whoop · Garmin · Fitbit
iPhone, United States App Store
Then $12.99 a month or $99.99 a year. Billed by Apple. Cancel any time.
No. CircadiaOS is a wellness app, not a medical device, and it does not diagnose or treat anything. It changes the temperature of your bedroom through the night using the smart thermostat you already own. If night sweats are new, severe or come with other symptoms, talk to your clinician.
On Premium, you can tell the app you are perimenopausal or postmenopausal. It then starts the two later phases of the night 1°F warmer than the standard starting curve, and it waits a full 14 nights before keeping any change it tries. That is all it does differently. It does not make the room colder by default, and you can take the whole curve cooler yourself at any time.
Not automatically on night one. The starting curve is conservative. You can tap the whole curve cooler in the app, one degree at a time, and set the coolest temperature you are comfortable with (the app goes as low as 63°F). On Premium with a wearable, CircadiaOS also tries cooler settings one phase at a time over the following weeks and keeps the ones your nights back up.
The free plan gives you a starting overnight schedule you can set on any programmable thermostat by hand, plus your wearable's nightly data. Automatic control needs a Wi-Fi smart thermostat such as ecobee, Honeywell Home or Sensi. If you are buying one, check the compatibility page first.
One thermostat sets one room, so you share the curve. What helps is the shape: cooler early in the night, then warmer before you wake, which is when a cold sleeper is most likely to notice. Separate blankets make the biggest difference for couples. If you both wear trackers, connect the one belonging to whoever is more bothered by temperature. More in couples and the thermostat.
No. The four-phase schedule runs without one. A wearable (Apple Watch, Oura, Whoop, Garmin or Fitbit) is what lets Premium try changes and keep the ones that fit you.
There is a free plan. Premium, which controls your thermostat automatically and learns from your wearable, is $12.99 a month or $99.99 a year after a 2-week free trial, billed through the App Store. Cancel any time.
No. It is a way to stop your bedroom being stuck on one temperature all night. It works alongside whatever you and your clinician decide.
Two minutes to set up. Nothing to buy. Two weeks of Premium free.
CircadiaOS is a wellness product, not a medical device. It is not intended to diagnose, treat, cure or prevent any disease or condition. Research cited on this page describes published findings about menopause and body temperature, not results from CircadiaOS.
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