Thermio technical specs
Detailed specifications for hikers who want to dig deeper into sensors, accuracy, logging, battery, environmental limits, app features, and validation status.
Some values below are validated component specifications, some are pre-production product targets, and some are still in development. Final production specs will be confirmed before launch.
Sensors and measurement
Temperature
±0.1 °C typical accuracy (sensor specification)
−30 to +60 °C operating range
Validated component spec. Actual product accuracy may vary with enclosure and airflow conditions.
Humidity
±0.5 %RH typical accuracy (sensor specification)
0–100 %RH
Below approximately −20 °C, humidity readings may show reduced confidence.
Barometric pressure
±0.2 hPa absolute accuracy (sensor specification)
260–1260 hPa
Useful for pressure trend detection and altitude estimation.
Calibration and traceability
Thermio is built on a factory-calibrated sensor with documented traceability:
Each sensor is individually trimmed at the factory — accurate out of the box, with no user calibration required.
Calibrated against references traceable to NIST standards.
Reference calibration carried out under ISO/IEC 17025.
Logging and data
- Default logging interval: 15 seconds (configurable via app)
- On-device data storage with BLE sync to the companion app
- On-device memory holds roughly 200 days of logging at the default 15-second interval on real hiking data, and about 51 days in a realistic worst case
- Historical graphs and trend views in the app
- CSV export for full data logs
- Each paired sensor is tracked and displayed separately in the app
App capabilities
The companion app connects to your sensors via Bluetooth.
- View current temperature, humidity, and pressure readings
- Browse historical graphs and pressure trends
- Track each paired sensor separately with individual data views
- Use Thermio and Thermio Mini together — the app shows both sensors’ values and graphs in one place
- Export data as CSV for your own analysis
- Set custom alert thresholds for temperature, humidity, and pressure changes (coming soon)
- Available in 10 languages
Available for iOS and Android.
Power and battery
- Thermio: CR2032 coin cell — around 2 years of runtime with logging active and Bluetooth on
- Thermio Mini: CR1632 coin cell — around 2 years of runtime with logging active and Bluetooth on
Runtimes refer to normal use — the sensor logging at the default interval with Bluetooth enabled. Measured on production hardware. Actual life also depends on logging interval and how often you sync. User-replaceable coin cell.
Environmental and durability
- Operating temperature: −30 to +60 °C
- Water resistance: in development — no rating claimed yet
Enclosure sealing is still in development, so we are not claiming a water-resistance rating and have not set one as a target. The enclosure is designed for rain, splashes, and exposed trail use, and is not intended for submersion. If we reach a rating we can stand behind, we will publish it here.
Cold-tested to −20 °C. Pressure and temperature sensors perform well in cold conditions. Humidity accuracy may decrease below −20 °C.
Designed for trail use — clip it to your pack, guyline, or carabiner and leave it in the weather.
Connectivity
- Bluetooth Low Energy (BLE) sync with the companion app
- Sensor operates independently — no phone needed for on‑device readings or data logging
- Sync when in range to transfer stored data to the app
Physical specs
- Thermio weight: 9 g (target)
- Thermio Mini weight: 5 g (target)
- Thermio display: 1.28″ reflective memory LCD + bonded Gorilla Glass
- Thermio Mini: no display — data accessed via app
- 3D-printed enclosure
Validation and testing status
Sensor accuracy (T/RH/P)
Component-level sensor specs confirmed
Cold testing
Tested to −20 °C in real alpine conditions
Field testing
Multiple field units tested on real trails
Water resistance
Sealing still in development — no rating claimed or targeted yet
Battery life
Around 2 years for both sensors with logging and Bluetooth on — measured on production hardware
App + BLE sync
Working BLE connection with companion app
Data logging + CSV export
Configurable logging with CSV export tested
Reflective memory LCD
Sunlight-readable display verified in field conditions
Ready to get early access?
Join the waitlist for the founder price (€59 Mini / €109 Thermio) and product updates.
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