The altitude (in metres above sea level, MASL) at which a coffee was grown. Specialty bags routinely print this — "1,800 MASL," "1,950 MASL" — because elevation is one of the strongest predictors of cup quality in arabica.
Why elevation matters
Coffee cherries ripen more slowly at altitude. Lower temperatures and a wider day-night swing mean the cherry takes longer to develop, and the bean inside accumulates more sugar, more density, and more of the precursor compounds that become aromatic complexity in the roasted cup.
A coffee grown at 1,000 MASL and the same variety grown at 1,800 MASL won't taste similar. The high-grown bean will be denser, harder, more acidic, and more aromatically complex. The low-grown bean will be softer, simpler, lighter in cup.
Rough thresholds
- Below 1,200 MASL: typically commercial-grade arabica or robusta territory. Cup is mild, low-acid, low-complexity.
- 1,200–1,500 MASL: solid specialty range. Many balanced Brazilian, Mexican, Vietnamese arabica origins.
- 1,500–1,800 MASL: high-grown specialty. Bright acidity, articulate aromatics. Most Colombian, Costa Rican, Salvadoran lots.
- Above 1,800 MASL: very high. Dense beans, intense flavors. Top Ethiopian, Kenyan, Panamanian Geisha territory.
These are guidelines, not rules. Origin and variety also matter — a 1,400 MASL Ethiopian heirloom can outperform a 2,000 MASL bulk Colombian. But within an origin and variety, higher generally means more interesting.
What it means for brewing
High-grown beans are denser and harder, which means they typically need slightly longer extraction — finer grind or hotter water — to fully develop in the cup. Low-grown beans are softer and extract faster; over-extracting them muddies the cup quickly.