testo 623 - Thermohygrometer

Order-Nr.  0560 6230

  • Measures room temperature / humidity / alerts the occupants when thresholds are reached

  • Large, easy to read display / shows current reading / provides at-a-glance 90-day statistic snapshot

  • Long term stable sensor for long term / high quality readings

  • Table and wall mount included

The elegantly designed testo 623 thermohygrometer measures the temperature and humidity in offices, living spaces, and commercial premises, and logs the readings for 90 days.

Product Description

The compact and elegant testo 623 is designed to grace any desk, table, or wall, and provide reliable temperature and humidity readings in offices, living spaces, and commercial premises.

The testo 623 thermohygrometer – technical features

The testo 623 thermohygrometer measures the indoor temperature and humidity accurately and reliably. User-defined settings allow you to determine the length of the intervals – from 5 minutes to 24 hours. The readings are saved for 90 days, and an alarm warns when thresholds are reached.
The large, easy to read display shows the last reading, time, and date, and a 90-day statistic, which allows you to carry out a long-term analysis of the indoor temperature or humidity without accessing your PC.
The testo 623 thermohygrometer has a long term stable sensor that guarantees long term, high quality readings, and is elegantly designed to fit seamlessly into any environment. It can be placed on a desk or table like a photo frame, or fixed to a wall. A table and wall mount are both included.


Delivery Scope

testo 623 thermohygrometer, batteries, calibration certificate, and table and wall mount
Temperature - NTC

Measuring range

14° to 140 °F / -10 to +60 °C


±0.7 °F / ±0.4 °C


0.1 °F / 0.1 °C

Humidity - Capacitive

Measuring range

0 to 100 %rH*


±2 %rH at +77 °F (10 to 90 %rH) / ±2 %RH at +25 °C (10 to 90 %RH)

±3 %rH Remaining Range


0.1 %rH

* Not for condensing atmospheres. For continous use in high humidity (>80 %RH at ≤30°C for >12 h, >60 %RH at >30°C for 12 h), please contact us via our website.

General technical data


7 x 4 x 1 in. / 185 x 105 x 36 mm

Operating temperature

14° to 140 °F / -10 to +60 °C

Measuring rate

20 sec



Protection class




Battery type

4 x AA batteries

Battery life

12 Months

Storage temperature

-4° to 140 °F / -20 to +60 °C


8 oz. / 240 g