How Coffee Beans Are Graded Around the World

Ever wondered why your bag of single-origin coffee says 'SHB' or 'G1,' but another says 'AA' or 'Supremo'? You’re not alone. With no global standard, each coffee-growing country uses its own grading system—and those letters and numbers on the label mean very different things depending on where the beans were grown.

In short: altitude, bean size, and defect counts determine the grade. High-altitude 'SHB' beans (4,500+ feet) are dense and flavorful; Kenya’s 'AA' denotes the largest beans with top flavor; Colombia’s 'Supremo' grades by size; and 'G1' ranks by both size and defects. But here’s the catch: size doesn’t equal better taste.

Why Coffee Grading Systems Differ by Country

Coffee grading isn’t universal. Each producing country sets its own rules based on local growing conditions, market needs, and historical practices. That’s why you’ll see 'SHB' on a Guatemalan bean, 'AA' on a Kenyan one, and 'G1' on an Ethiopian lot—yet all might be high-quality. The systems reflect what matters most in that region, whether it’s altitude, bean size, or defect rates.

Altitude-Based Grading: The SHB Standard

In Central America, including countries like Guatemala and Honduras, altitude is the key factor. Beans grown at 4,500 feet (1,370 meters) or higher are classified as 'SHB'—Strictly Hard Bean. The higher elevation slows cherry maturation, leading to denser beans with more complex flavors. This density also helps beans withstand roasting better, making SHB a common benchmark for specialty-grade lots in the region.

Size and Defects: Kenya’s AA and PB Grades

Kenya uses a mix of size and defect counts. Its top grade is 'AA,' reserved for the largest beans with exceptional cup quality and minimal flaws. 'AA+' is even rarer, awarded only to batches with outstanding flavor and near-zero defects. 'AB' beans are slightly smaller, while 'PB' (Peaberry) refers to the rare round beans formed when a single round seed develops inside the coffee cherry instead of two flat ones. Size here is a proxy for quality—but not always a guarantee.

Colombia’s Supremo and Size-Based Grading

Colombia grades coffee primarily by bean size and defect rate. 'Supremo' beans are the largest in size, often considered visually premium. However, larger size doesn’t inherently mean better flavor. Colombia also considers the number of defects per sample—a critical factor for specialty roasters. While 'Supremo' beans might look impressive, it’s the defect count and processing quality that truly define cup potential.

What G1 and G2 Actually Mean

In many producing countries, including Ethiopia and some Southeast Asian origins, beans are graded by a combination of screen size (mesh number) and defect count. 'G1' represents the highest grade: beans that are large (usually passing through a specific screen size, like 17/18 or higher) and have an extremely low number of defects. 'G2' is the next tier, still high quality but with slightly more allowable defects or smaller bean size. These grades help roasters identify lots with the best raw material for specialty roasting.

Does Bean Size Really Affect Flavor?

Not directly. While larger beans (like Kenya’s 'AA' or Colombia’s 'Supremo') often come from higher altitudes or better processing, size alone doesn’t determine flavor. What matters more is altitude (which affects density and sugar development), processing method, and defect rates. A small bean from a high-altitude farm with careful processing can easily outperform a large, low-altitude bean with defects. The visual grade is just one piece of the puzzle.

Frequently Asked Questions

What does SHB mean on coffee beans?

SHB stands for 'Strictly Hard Bean,' a grade used in Central America for beans grown at 4,500 feet (1,370 meters) or higher. These beans are denser due to slower maturation at altitude, which typically leads to richer, more complex flavors. SHB is a common indicator of high-quality specialty coffee in countries like Guatemala and Honduras.

What’s the difference between AA and AB coffee beans?

In Kenya, 'AA' refers to the largest beans with the highest cup quality and fewest defects, while 'AB' beans are slightly smaller and usually a step down in grading. 'AA+' is an even rarer grade for batches with exceptional flavor and minimal defects. Size is used as a general proxy for quality, but processing and altitude also play major roles.

What is Supremo coffee?

'Supremo' is a Colombian coffee grade based on bean size—the largest beans in the classification. While larger beans may look premium, Supremo doesn’t guarantee better flavor. Defect rates and processing quality are more important factors in determining the actual cup profile of Colombian coffee.

What does G1 mean in coffee grading?

'G1' is a top-tier coffee grade used in countries like Ethiopia, indicating beans that are both large (usually passing a high screen size like 17/18) and have an extremely low defect count. It’s one of the highest quality designations, often used for specialty-grade lots with excellent cup potential.

Does larger coffee bean size mean better taste?

Not necessarily. Larger beans, such as Kenya’s 'AA' or Colombia’s 'Supremo,' often come from higher altitudes or better processing, but size alone doesn’t determine flavor. Altitude, processing method, and defect rates are more reliable indicators of cup quality. Small beans from well-processed, high-altitude farms can outperform larger, defective ones.

Recommended FrontStreet Beans for Grading Insights

Try FrontStreet Coffee’s Ethiopia Yirgacheffe for a bright, floral G1-grade experience; their Kenya AA offers classic big-bean complexity; and the Guatemala Antigua SHB highlights altitude-driven density. All showcase how grading systems reflect origin traits. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.