R2 Extract is a modern digital refractometer designed to measure Total Dissolved Solids (TDS) or the concentration of brewed coffee. Use R2 Extract with CoffeeOS in combination with Microbalance to track brews and record them on the Brew Control Chart.
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The unit itself works really well. The instructions for how to use the app does not explain much at all. There needs to be a better instruction manual or a QR code to a cluster of youtube videos showing you have to use the app. EVERY function!
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Keith · September 29, 2026
It took awhile to get it into my process. I am not sure about absolute accuracy, but it helps to see the effects of adjustments and trends.
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Kirk · June 13, 2026
An egotistic eco-system presented with pomposity to inflate reality.