Starting at $534.00

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  • Humidity Measurements:
    • Range; 0 to 100 %RH
    • Accuracy; ±1.5 %RH (0-90 %RH), ± 2.5 %RH (90-100%RH)
    • Sensor; HUMICAP® 180R
  • Temperature measurement:
    • Range; 14 to 140°F (-10 to 60°C)
    • Accuracy; 0.36°F (±0.2°C), 0.72°F (±0.4°C)
    • Sensor; Pt1000 RTD
  • Large graphic display
  • Displays a wide range of quantities: RH, T, Td, Tw, a, x, h
  • Compact and robust housing
  • Hold-button to freeze the screen
  • Multilingual user interface with 10 languages
  • Interchangeable HMP113 probe
  • Can be user calibrated
  • Powered by standard AA batteries

What's in the Box

  • Belt clip
  • Case
  • NIST certificate of calibration

The Vaisala HM40 Humidity and Temperature Meter is a compact and portable humidity meter at hand everywhere you go. It is an ideal spotchecking tool that is easy to use and provides reliable measurement. It can be used for a wide range of various portable measurement applications. According to a user's needs, the meter is available in two models: standard and with a remote probe.

The HM40 includes a user-friendly, large graphical display and easy-to use push buttons. The user interface is simple and intuitive to use, and available in 10 languages. Also, many other settings can be modified by the user to best suit his individual needs. In addition to relative humidity and temperature, the HM40 provides five calculated humidity parameters, all available in both metric and non-metric units. Vaisala HMK15 Humidity Calibrator.

The HM40 is powered by 2 AA batteries. An external NiMH charger with USB connection and rechargeable AA sized NiMH batteries are available as an option. Each model also comes with a handy belt clip and case.


Vaisala HMP113 Humidity Probe
Measurement probe with plastic grid filter for Vaisala HM40 Humidity and Temperature Meter


Vaisala USB Battery Recharger
2 AA-size NiMH batteries and USB charger


Please consider these optional accessories.

Vaisala HM40 Probe Handle and Cable
Probe handle and cable for the Vaisala HM40 Humidity and Temperature meter
Vaisala Probe Attachment Nut
Plastic nut for attaching the Vaisala HMP113 probe to the Vaisala HM40 indicator
Vaisala Sensor Filter with Membrane
Sensor filter Ø12mm, plastic grid with membrane
Vaisala Sensor Filter
White PC plastic protective grid with Ø12mm female thread filter grid for HM40, HMP113 and HMP155
Vaisala Belt Clips
3 spare belt clips for Vaisala HM40 Humidity and Temperature meter
Vaisala Battery Cover
Plastic battery cover lids for HM40, 3pcs