PM2.5
PM10
01 · CLEANER AIR
Know when to run the purifier.
Spot rising particles, start filtration and see when the air clears.
Terrestream · Indoor air quality sensor
Breathe better
at home.
Know when to open a window, run a purifier or give the AC a break. Terrestream combines indoor readings with outdoor conditions to guide you.
See the CO₂ display and status light
Free iOS & Android app + web dashboard
The Terrestream app
Know what
to do next.
Run the purifier before cooking.
Close the windows before rain.
Get timely reminders, then follow your readings to see what changes.
See how it fits your day ↓Free iOS & Android app + web dashboard30-day returns1-year limited warrantyFree shipping
At home with Terrestream
Everyday life changes your air.
01 / 12
CO₂
02 · HOMEWORK TIME
Make fresh air part of the routine.
See CO₂ rise during homework, then air out when outdoor conditions allow.
Temperature
Outdoor humidity
Outdoor air
03 · LOWER COOLING COSTS
Give the AC a break.
Find cool, clean evenings to pause the AC and let outside air do the work.
Outdoor smoke
PM2.5
04 · SMOKE OUTSIDE
Keep smoky air outside.
Outdoor smoke alerts help you know when to close windows and filter indoors.
CO₂
05 · THE BEDROOM
Find out what builds up overnight.
Check overnight CO₂ patterns and plan a chance to air out before bed.
PM2.5
06 · BEFORE DINNER
Start the filter before the first sizzle.
Get a reminder to start filtration ten minutes before cooking.
Outdoor pollen
07 · POLLEN SEASON
Pollen can change the plan.
Check local pollen conditions before opening the windows.
Humidity
08 · AFTER A SHOWER
See when the room is back to normal.
Follow humidity after a shower and see when the fan has done its job.
PM2.5
PM10
09 · AFTER CLEANING
Check the air after cleaning.
Get a reminder to air out after vacuuming, when outdoor conditions allow.
Rain & wind
10 · WEATHER CHANGES
Close up before the rain.
A timely reminder helps you close the windows before the weather turns.
Outdoor temperature
Outdoor humidity
11 · OUTDOOR MOISTURE
Cooler outside isn’t always better.
Avoid bringing in moisture your AC will have to remove. Check humidity before opening up.
VOC Index
12 · SOMETHING NEW
See what changes after a delivery.
Follow the VOC Index after unpacking, then air out when outdoor conditions allow.
Terrestream Intelligence
Open your windows
at the right time.
Rising CO₂ calls for fresh air. Outdoor pollution can change the plan. Terrestream considers both.
Interactive example
When to air out
Inside your room
CO₂ is risingFresh air would help
Outside your home
High particlesMild weather
Terrestream recommends
Keep windows closed.
Use filtration for particles. Air out when outdoor conditions improve.
Filtration does not lower CO₂.
Outdoor particle levels
Recognizes
over 100 situations.
From cooking and cleaning to a change in the weather.
Air pollution
Smoke
Pollen
Temperature
Humidity
Rain & wind
Built to measure what matters
One device. Six sensors.
Twelve signals.
Dedicated CO₂ sensing and laser particle detection help you follow the changes that ventilation and filtration make.
Your indoor air
CO₂
Carbon dioxide
PM2.5
Particles ≤ 2.5 µm
PM10
Particles ≤ 10 µm
IAQ
Calculated air quality index
VOC Index
Organic gas changes
NOₓ Index
Oxidizing gas changes
PM1.0
Particles ≤ 1 µm
PM4.0
Particles ≤ 4 µm
Temperature
Room warmth
Humidity
Moisture in the air
Pressure
Barometric pressure
Ambient light
Room brightness
Sensing technology from Sensirion, Bosch and Texas Instruments.
See the measurement evidence ↗A clear picture of ownership
Start with
one room.
- Terrestream sensor, power adapter & USB-C cable
- Free app & web dashboard
- Core recommendations, notifications & 90-day history
No subscription required.
Is there an ongoing fee?
The app, web dashboard and core recommendations are included. Pro is optional and adds features such as longer history.
Compare included and Pro features ↗
Does one sensor cover my whole home?
Each sensor measures the room it is in. Add sensors where you sleep, work or spend time, and compare them in the app.
What does it need to work?
Plug it into USB-C power for local readings. Connect to Wi-Fi and create an account for the app and connected guidance.
Does it clean the air?
It measures your air and helps you decide when to ventilate or filter. You take the action. It does not replace a purifier, smoke alarm or carbon-monoxide alarm.
$249 USD per sensor
Make room for better air™
30-day returns · 1-year limited warranty
Buy Terrestream · $249 ↗Free shipping to the US, Canada & Mexico