Agtron Scale

The Agtron scale is the industry standard for measuring the color of roasted coffee beans. Developed by the Agtron company, this system uses near-infrared light to analyze the reflectance of the coffee surface. The resulting number provides a precise, objective measurement of how dark or light a roast is, moving beyond subjective terms like 'medium' or 'dark' which can vary wildly from one roaster to another.

On the Agtron scale, lower numbers indicate a darker roast, while higher numbers indicate a lighter roast. For example, a very dark, oily French roast might have an Agtron value in the 25–35 range, while a light, bright Scandinavian-style roast might fall in the 75–85 range. This numerical precision is essential for quality control in professional roasteries, as it allows roasters to replicate their roast profiles with high accuracy and communicate their roast levels clearly to wholesale customers and quality control teams.

For the coffee professional, the Agtron scale is more than just a color measurement; it is a tool for consistency. By tracking the Agtron number of every batch, a roaster can ensure that the coffee they sell today tastes the same as the coffee they sold last month. It also helps in the development of new roast profiles, as roasters can correlate specific Agtron numbers with the sensory results found during cupping, allowing them to dial in the perfect roast for a specific bean.

In practice, you will often see Agtron numbers on professional coffee bags or in technical roast logs. For the consumer, understanding the Agtron scale can help you better predict the flavor profile of a coffee. If you know you prefer a lighter, more acidic cup, you might look for coffees with higher Agtron numbers. If you prefer a deeper, more chocolatey, and less acidic cup, you might gravitate toward coffees with lower Agtron numbers. It is the roaster's way of being precise, ensuring that the coffee you buy meets the exact specifications intended by the producer and the roaster.