Refractometer HM


Precise, functional and connected to your smartphone via bluetooth, the HM Digital refractometer is the perfect tool to precisely control all your extractions.


Everything you want to know

The refractometer is a digital instrument that allows you to measure the refractive index of a liquid. In the scientific measurement of coffee extraction, this is used to accurately calculate the concentration of dissolved solids within the beverage, the TDS.

This parameter, together with our brew ratio, is essential to calculate the extraction percentage of the bean to accurately assess whether the extraction is correct, over-extracted or under-extracted and modify the parameters accordingly.

This refractometer is also equipped with an LCD display and three buttons that allow you to use all the available functions and choose the reading scale between Brix and TDS.

Furthermore, by downloading the dedicated app for Android or IOS, you can connect the refractometer with your smartphone via bluetooth to save all the data and have a clear view of your extraction on the Brew Chart.

If you measure coffee samples extracted with methods that use metal filters (such as espresso and French Press ...) always filter the samples with a paper filter before measuring.

The refractometer is designed for the professional barista who wants to scientifically monitor all the parameters of the coffee extraction.


  • Unit of measure: Brix, TDS, Temperature
  • TDS resolution 0.01%
  • TDS accuracy 0.02%
  • Measurement time within 5 seconds
  • Automatic shutdown after 2 minutes
  • Automatic screen brightness control (20 seconds)
  • Use environment 10 ° / 40 °
  • Inactive sample volume 0.5ml
  • Power source 1.5Vx2 (AAA alkaline)
  • Dimensions: 58 (W) x 36 (D) x 122 (H) mm
  • Weight: 149g (including batteries and removable cover)
  • Wireless: Bluetooth technology
  • Use the HM Coffee mobile application


Download now:
Click for ANDROID
Click for IOS
The App is currently not available in North America and South America

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