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Sonin 50218 Moisture Meter
Our Score:
Delmhorst BD2100 Moisture Meter At A Glance

This meter exhibits a critical flaw—namely it appreciably under-reports moisture content in wood below about 12% moisture content. This flaw renders the meter essentially unusable for a number of common applications, including for flooring installations and furniture making. We deducted two stars from our overall rating to reflect this critical flaw.

As with all pin meters, it can be very difficult to insert the pins far enough into hardwoods to obtain accurate readings. Attempting to do so often results in bent or broken pins. Also, short pins will not reach far enough towards the center of thicker slabs where higher moisture is found. According to the United States Department of Agriculture, boards should be read at a depth of one-fourth to one-fifth of its thickness.

The Sonin 50218 is a pin-style wood moisture meter with a large, easy-to-read digital readout. It is designed to appeal to the budget-conscious user. Another attraction is that it is extremely simple to use.

However, the user should keep in mind that this meter has significant limitations and should not be relied upon for measuring wood with low MC levels even though it is supposedly designed to take measurements to 5% MC. The Sonin 51218 also lacks the capability of making adjustments for different species of wood.


  • Simple-to-use with large, easy-to-read LED display
  • Features data hold button
  • MC readings from 5% to 40%


  • Readings are not accurate below about 12% MC
  • Manual provides very little instruction about use
  • No adjustment available for wood species

Objective Evaluation – Overall Score 2.4 out of 5.0

Sonin 50218 Objective Test Summary

Accuracy – 3.3 out of 5.0

This meter provided reasonably accurate readings from about 12% through about 22% MC when compared to ASTM D4442 oven dry standards. Below 12% MC, this meter’s accuracy is questionable due to significantly low readings.

Splatter chart showing the Sonin 50218 wood moisture meter provides reasonably accurate readings from 12% to 22% MC

Learn about our accuracy test procedures

Surface Moisture – 1.0 out of 5.0

Surface moisture caused this meter to post readings over 10% higher than the baseline. These surface moisture results indicate that operating this meter in high humidity environments where condensation may form on the surface could lead to questionable readings.

Bar chart showing surface moisture caused the Sonin 50218 meter to post readings over 10% higher than the baseline.

Learn about our surface moisture test procedures

Meter Temperature – 2.0 out of 5.0

Meter temperature had a significant effect on this meter’s MC readings. A low meter temperature of 34.8° F in the presence of low MC decreased the reading by 1%, while in the presence of high MC, the reading decreased by 2% compared to the room temperature reading. A high meter temperature of 110° F in the presence of high MC, increased the reading by about 2% MC.

Sonin 50218 Meter Temperature

Learn about our meter temperature test procedures

Wood Temperature – 3.7 out of 5.0

Wood temperature affected this meter’s readings.

A low wood temperature of 33.6° F in the presence of low MC showed a 3% decrease in the reading when compared to the room temperature reading. In the presence of high MC, the reading did not change appreciably.

A high wood temperature of 110° F in the presence of low MC showed a 2% increase in the reading when compared to the room temperature reading. In the presence of high MC, the reading increased by about 1%.

Sonin 50218 Wood Temperature

Learn about our wood temperature test procedures

Reading repeatability – 3.0 out of 5.0

The readings of this meter were not entirely repeatable, showing some tendency to vary.

Line chart showing the readings of the Sonin 50218 wood moisture meter were not entirely repeatable

Learn about our repeatability testing procedures

Drift – 1.0 out of 5.0

Readings for this meter showed a significant tendency to drift, with readings that were lower by about 1% MC after 3 seconds.

Sonin 50218 Drift

Cable Interference – N/A

This meter does not offer cabled accessories so the cable interference test could not be conducted.

Sonin 50218 Cable Interference

Learn about our cable interference and drift testing procedures

Subjective Evaluation – Overall Score 3.0 out of 5.0

Sonin 50218 Subjective Test Summary

Learn about our subjective testing procedures

Ease of Use – 2.8 out of 5.0

With only a power button and hold button to push, this meter is fast and simple to operate with very little use of the manual needed to get started. However, documentation in the manual is limited.

Quality – 2.3 out of 5.0

This meter is intended for the budget-conscious individual, and it shows. The meter casing is basic, no carrying case is provided, and the pins are subject to bending or breaking.

Comfort – 3.5 out of 5.0

This meter has a large LCD display that is extremely easy to read. The meter’s tear-dropped shape is convenient for holding and obtaining readings.

Versatility – 1.0 out of 5.0

This is a pin-style meter that is not capable of adjusting for species, nor is it intended for use with other building materials.

Range – 5.0 out of 5.0

Measures moisture content from 5% to 40%, at least in theory. However, our testing revealed that this meter significantly underestimates wood moisture below about 12% MC.

Features – 2.1 out of 5.0

Readings precise to the nearest 0.1%. Low battery indicator. Simple-to-use with one-button control. Offers a HOLD function for use in tight spaces where the display cannot be easily viewed.

Customer Service – 4.0 out of 5.0

Sonin offers free replacement if anything goes wrong in the first year. No service center is available for repairs primarily due to the fact that it is an inexpensive unit. No calibration services are available.

Response to telephone inquiries is immediate and extremely friendly.


Our review is based on Moisture Meter Experts independent evaluation of the meter, which was purchased by Moisture Meter Experts or provided free of charge by the manufacturer. By purchasing this meter through the links above, Moisture Meter Experts may be compensated either by your purchase directly from Moisture Meter Experts or from commissions from an affiliate. View our Review Procedures section to learn more about our proprietary evaluation procedure and expertise in the field of moisture meters.