What is Agtron and how is it used in roasting?

Agtron is a numerical scale used to measure roast level by analysing the colour of roasted coffee - either ground or whole bean - using a spectrophotometer that measures near-infrared light reflectance. The scale runs from 0 (very dark) to 100 (very light). A higher number means a lighter roast.

Specialty roasters typically work in the range of roughly 45–75 on whole beans, depending on their target profile. Agtron is particularly useful for production consistency - roasting the same coffee to the same Agtron score batch after batch gives you a repeatable, objective reference point that taste alone can't always provide. If your Colombia profile reads 63 today and 58 next week with no change to the recipe, something in your process has drifted.

"Agtron" refers both to the company that developed the system and the scale itself. Third-party devices - including many modern roast colour meters from companies like Tonino and Colourette - produce Agtron-equivalent readings and are widely used across specialty roasteries. The SCA has incorporated the Agtron scale into its roast classification system.