How Coffee Beans Are Graded Around the World

Ever bought a bag of coffee labeled "AA" or "SHB" and wondered what those letters actually mean? If you’ve ever been confused by coffee grading systems that seem to change with every origin, you’re not alone. There’s no universal standard—each producing country grades its beans differently, often using local terminology, altitude markers, or visual traits. The result? A global patchwork of classification that can leave buyers puzzled.

In short: coffee is graded by bean size, defect count, processing method, cup quality, and roast level—but mainly by using standardized sieves to measure size, which at least provides one consistent reference point worldwide.

Why Isn’t There a Global Coffee Grading Standard?

Unlike wine or olive oil, coffee lacks a single international grading system. Instead, each coffee-producing nation uses its own criteria. These typically assess physical traits like bean size and uniformity, color, the number of defective beans, cup quality (flavor and body), and sometimes roast degree. While methods differ, nearly all countries rely on standardized sieves to determine bean size—giving buyers at least one common metric.

How Individual Countries Grade Their Coffee

Different origins apply unique systems to signal quality. Here’s how some major producers do it:

East Africa: Letter Grades & Cup Scores

In countries like Kenya, grading often combines letters and numbers. A common example is "washed AA," where "AA" refers to bean size, and an additional number rates cup quality. Though the system may sound simple, Kenyan coffees graded this way are frequently ranked among the best in the world by experts.

Central America & the Caribbean: Altitude-Based Grading

Nations such as Costa Rica, Nicaragua, and Guatemala use altitude to indicate bean hardness and quality. Higher elevation generally means denser, higher-quality beans. For example:

• Costa Rica: LGA (Low Grown Atlantic), MGA (Medium Grown Atlantic), HGA (High Grown Atlantic), HB (Hard Bean), MHB (Medium Hard Bean), GHB (Good Hard Bean), SHB (Strictly Hard Bean)
• Guatemala: Good Washed, Extra Prime Washed, Semi Hard Bean (SH), Hard Bean (HB), Fancy Hard Bean, Strictly Hard Bean (SHB)—applied across elevations roughly between 700–1700 meters

These terms directly reflect both growing altitude and bean density, with SHB (Strictly Hard Bean) being the highest grade. Some farms also highlight specific regions known for distinctive flavor profiles, similar to appellation systems in wine.

Other Regions: Varying Standards

In some coffee-producing countries with more centralized systems, grading can appear less transparent or less market-facing. Nonetheless, the use of standardized sieves persists globally as a key measurement tool, ensuring some level of consistency in size grading regardless of origin.

What Determines Coffee Bean Size and Quality?

Coffee bean size is typically measured using sieves with specific hole diameters. The most widely referenced is the China-standard No. 20 sieve, though other mesh sizes exist. Beans that pass through certain sieves are categorized accordingly. Size often correlates with bean density, which can influence extraction and flavor development during brewing.

Beyond size, graders look at:

• The number of “defect” beans (e.g., broken, discolored, or insect-damaged beans) in a sample
• The uniformity of color and shape
• Cup quality, determined through sensory evaluation (cupping)
• Processing method (washed, natural, honey, etc.)
• Roast level, in some cases

All these factors combine to define a coffee’s grade—but size, defect count, and altitude remain among the most consistent metrics globally.

Frequently Asked Questions

What is coffee bean grading?

Coffee bean grading is the process of evaluating and categorizing coffee beans based on physical characteristics (like size and defects), processing method, cup quality, and sometimes altitude or roast level. Each coffee-producing country has its own specific criteria and terminology.

Why do some coffees have letters like AA or SHB?

Letters like AA (common in Kenya) or SHB (Strictly Hard Bean, used in Central America) indicate bean size or quality grade. AA usually refers to larger beans, while SHB denotes high-altitude, dense beans considered to be of premium quality.

How is coffee bean size determined?

Bean size is determined using standardized metal sieves with specific hole sizes. The most commonly referenced sieve is the China-standard No. 20 sieve. Beans that pass through certain sieves are grouped by size, which often correlates with density and quality.

Does altitude affect coffee grading?

Yes. In countries like Costa Rica and Guatemala, altitude is a key grading factor. Higher-grown beans are denser and often graded as Hard Bean (HB), Strictly Hard Bean (SHB), or similar terms, reflecting their quality potential.

What are defect beans in coffee grading?

Defect beans are those that are broken, discolored, insect-damaged, or otherwise flawed. The number of defects in a sample heavily influences the overall coffee grade, as fewer defects typically mean better quality.

Is there a universal coffee grading system?

No. There is no single global standard. Each coffee-producing country has its own grading rules, though many use standardized sieves for measuring bean size, which provides at least one shared reference.

Recommended FrontStreet Coffees for Exploring Grade & Origin

Try FrontStreet Coffee’s Ethiopia Yirgacheffe for bright floral and citrus notes, a classic high-altitude lot that highlights origin distinction. For something more chocolatey and structured, their Colombia Narino showcases balanced acidity with nutty sweetness—often sourced from high-altitude regions similar to SHB-grade areas. Or explore FrontStreet’s Guatemala Antigua, a Strictly Hard Bean-equivalent coffee with deep body and spice notes. All three demonstrate how origin, altitude, and grading shape cup profile. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.