Screen 16 and screen 18 refer to green coffee bean size measured on graded screens: screen 16 beans are retained on a 6.35 mm hole, screen 18 beans on a 7.14 mm hole. The 0.79 mm gap signals larger, more uniform beans — often reserved for differentiated Kintamani lots that roast evenly and command higher prices.
Green coffee buyers see “screen 16” and “screen 18” on nearly every offer sheet, yet the two numbers describe something deceptively simple: how wide a bean is. Reading the gap between them correctly helps a roaster judge a Kintamani lot and pay the right money for the right coffee.
How is coffee screen size actually measured?
Screen size comes from stacked metal sieves with round holes, each graded in increments of 1/64 of an inch (about 0.397 mm). Green beans tumble across the screens, and the number on a lot is the screen a bean sits on top of — not the one it drops through. A “screen 18” bean rests on an 18/64-inch hole.
Sorting beans this way is the foundation of coffee screen size grading, and it gives buyers a shared language across origins. The scale runs from small, peaberry-range beans up through the largest screen 19 selections.
| Screen number | Hole diameter | Typical role |
|---|---|---|
| Screen 14 | 5.56 mm | small beans, often blended down |
| Screen 15 | 5.95 mm | below the specialty baseline |
| Screen 16 | 6.35 mm | specialty entry point |
| Screen 17 | 6.75 mm | premium single-origin |
| Screen 18 | 7.14 mm | large, differentiated microlots |
| Screen 19 | 7.54 mm | showcase / competition size |
The move from screen 16 to screen 18 is two increments, roughly 0.79 mm of extra bean width — small in absolute terms, but meaningful once you multiply it across a full 60 kg bag.
What separates screen 16 from screen 18 in the cup?
Here is the honest answer many origin marketers blur: screen size does not measure flavour. It measures dimension. A bright, citrus-forward Kintamani Arabica can arrive as screen 16 or screen 18 and still taste of the same volcanic terroir.
What size genuinely influences is roast behaviour. Larger, uniform beans absorb heat more predictably, so a tightly sorted screen 18 lot roasts with fewer scorched or under-developed beans. That consistency is why competition roasters and single-origin programs often chase the bigger screens.
| Attribute | Screen 16 | Screen 18 |
|---|---|---|
| Hole diameter | 6.35 mm | 7.14 mm |
| Market role | specialty baseline | differentiated premium |
| Roast uniformity | good | very even, slightly higher energy |
| Visual appeal | clean | large, impressive on the table |
| Price position | lower end of the band | upper end of the band |
Why does specialty prefer screen 16 and above?
Across Kintamani export listings, the specialty threshold sits at screen 16 or above, with strong lots showing a high proportion retained on screen 17–18. Below screen 16, size variability widens and roast defects climb, which is why most buyers treat 16 as the floor for a specialty-grade Kintamani.
Three practical reasons push the market this way:
- Roast evenness. Uniform beans develop at the same rate, protecting the delicate citrus acidity Kintamani is known for.
- Visual signalling. Larger beans read as premium on a roaster’s bench and in a retail bag, before the cup is even scored.
- Sorting discipline. A lot that holds a tight screen band usually reflects careful processing and hand-sorting, which tends to correlate with cleaner cups.
Note the word “correlates.” A large screen size is a promising sign, not a guarantee. Grade and cupping score still come from the lot’s own cupping report or COA — never from bean size alone, and never attached to a farm or cooperative name as fixed fact.
How much does screen size move the price?
Screen size is one lever inside a wider pricing picture that also weighs process, cupping score and harvest timing. As of 2026, indicative FOB reference points for Kintamani green coffee sit in a single band, and larger, differentiated screens push a lot toward the upper end.
| Category | Screen / score guide | Indicative FOB 2026 |
|---|---|---|
| Washed Grade 1 specialty | screen 16+, SCA ~82–84 | USD 8–11 / kg |
| Microlot / natural | SCA 84–87+, often screen 17–18 | USD 10–15+ / kg |
| Commodity | mixed, below specialty spec | ~USD 3.5–6 / kg |
These figures are indicative and move with harvest, quality and score; a firm quotation always confirms grade, cupping score, lot and MOQ. A single-screen sort — say, all screen 18 — usually costs more per kilogram than a broad screen 16+ lot, partly because pulling out only the largest beans lowers the usable yield per bag.
What does screen size look like on a Kintamani spec sheet?
Kintamani Arabica is grown in the Kintamani Highlands of Bangli Regency, in north-east Bali — around Ulian Village, Catur Village and the surrounding Subak Abian areas — anywhere else in NTT. On a typical washed Grade 1 export factsheet you will usually see:
- Screen size: 15–19, specialty suitability at 16+, high proportion on 17–18
- Grade: Grade 1 (some semi-washed lots listed as Grade 1 TP, triple-picked)
- Moisture: max 13%
- Defect value: max 11
- Cup profile: bright citrus, from a region often called the capital of Bali’s specialty coffee
Read together, these lines tell a buyer far more than screen size alone. When you compare a screen 16 offer with a screen 18 offer, check that the moisture, defect count, process and cupping score line up too. Only then is the size difference actually worth a price difference — and green (unroasted) coffee still ships the same way, in GrainPro and jute bags from Bali or Surabaya ports, whichever screen you choose.
Frequently Asked Questions
Does screen 18 coffee taste better than screen 16?
Not automatically. Screen size measures bean dimensions, not flavour. A screen 18 lot can cup lower than a well-sorted screen 16 if it was grown or processed poorly. Size mainly affects roast uniformity and visual premium; cup quality still comes down to terroir, processing and the lot’s own cupping score.
Can one Kintamani lot contain both screen 16 and screen 18 beans?
Yes. Most washed Kintamani exports report a screen range like 15–19, with a stated proportion retained on 17–18. Buyers wanting a tighter, uniform lot ask for a single-screen sort — all screen 18, for example — which costs more per kilogram because it lowers the usable yield per bag.
Is screen 18 worth paying more for as a roaster?
It depends on your program. Screen 18 suits single-origin or competition lots where visual size and even roasting justify a premium. For blends, screen 16 delivers the same Kintamani citrus character at a lower FOB price, so many roasters buy 16+ and reserve the larger screens for flagship offerings.