Benchtop Water Activity Meter

Not a "quick mode" reading or an approximation, but a direct measure of water activity accurate to 0.003


Speed and accuracy

Measure water activity in 5 minutes or less (average read time: 2.5 minutes) with ±0.003 aw accuracy. AQUALAB instruments are the fastest, most precise water activity meters available.

Use (almost) anywhere

Water activity meters must report a temperature because water activity is temperature-dependent. Internal temperature control lets you set a measuring temperature between 15 and 50 °C and use the instrument anywhere—even outside the QC lab.

Use the AQUALAB water activity meter 4TE to get lab-quality measurements at the line, receiving dock, processing plant, storage facility—anywhere you need to test and verify the safety and quality of your products and ingredients.

How it works

Put a 7.5 ml product sample in a disposable cup, place in the water activity meter, seal the sample chamber lid over the sample, and wait for vapor equilibrium.

An infrared beam focused on a tiny mirror determines the precise dewpoint temperature of the sample. That dewpoint temperature is then translated into water activity.

Easy to clean

The sample chamber lid flips up so contaminated sensors are quick to spot and easy to clean.

Secure data

The AQUALAB water activity meter 4TE stores time, date, and user information with every measurement and calibration, and can store up to 10,000 secure data points.

Administrative functions can be set to control access to data. Designate up to 25 unique users and passwords. Use the RS-232 serial data port to download or print data for statistical analysis and to maintain compliance records and archives.


Get pricing Connect your AQUALAB 4TE


  • Fast: water activity meter gets readings in 5 minutes or less
  • Accurate: ±0.003 aw
  • Verifiable with independent salt standards
  • Repeatable: different users, different locations, same result
  • Portable: weighs just 7 pounds
  • Easy to use: water activity meter yields precise measurements with minimal training
  • Secure: offers administrative control over calibration and sample data
  • Proven: used by 80 of the top 100 food companies


Sensor Type

Chilled mirror dew point

Water Activity Accuracy


Water Activity Resolution

0.0001 aw

Water Activity Range

0.030 − 1.000 aw

Water Activity Repeatability

0.001 aw

Measurement Time

Average of 5 minutes

Temperature Control

25 °C standard; 15 to 50 °C

Temperature Adjustment Increment

1 °C

Sample Temperature Accuracy*

±0.2 °C

Sample Temperature Resolution

0.01 °C

Temperature Stability

User-selectable range, internal thermoelectric controlled

Sample Dish Capacity

7.5 mL recommended (15 mL full)

Program Identification

Alphanumeric, Programmable to Display Product Name, Lot, or Product ID Number

Data Storage

8,000 readings

Data Communications

USB and RS 232 A serial, 9600 to 115200 baud


128 x 64-pixel graphical display with backlighting

Case Dimensions

26.7 x 17.8 x 12.7 cm

Case Material

POLYLAC PA-765 (ABS) with fire retardant


3.1 kg (6.83 lb.)


110 to 220 VAC, 50/60 Hz

Operating Environment

4 to 50 °C; 90% relative humidity (non-condensing)



UL Listed


One year, parts and labor

*Calibrated to a NIST traceable temperature standard



Have a question or problem? Our support team can help.

We manufacture, test, calibrate, and repair every instrument in house. Our scientists and technicians use the instruments every day in our product testing lab. No matter what your question is, we have someone who can help you answer it.


Phone: 509-332-5601