How Many Coffee Beans Per Cup? About 75 for a 6 oz Cup

About 75 roasted arabica beans make a 6 fl oz cup of coffee, and about 100 make an 8 fl oz mug, at the standard 55 g of coffee per liter of water (9.8 g and 13.0 g). Bean size and roast level shift the 6 fl oz count from about 60 to 100, so weigh your dose.

How many beans per cup of coffee?

How many coffee beans are in a cup of coffee depends first on the cup. In coffee, a “cup” is 6 fl oz, the unit behind the National Coffee Association’s Golden Ratio, and an 8 fl oz mug is the size of a US measuring cup. The table doses each serving at 55 g of coffee per kilogram of water, then divides by the weight of one roasted bean. The working follows below.

The headline is the spread, not the midpoint. A 6 fl oz cup is somewhere between about 60 and 100 beans, and where it lands depends on things nobody prints on a bag: bean size, variety, growing altitude and how dark the roaster went.

A measuring cup of whole beans is a different question. Weigh a level cup of your own beans once and divide by the bean weight below; a cup can hold fewer grams the darker the roast, because roasting lowers the beans’ density (figures under “Should you count coffee beans or weigh them?” below).

A “12-cup” machine isn’t a fixed size. Cuisinart’s DCC-1120 booklet describes a “60 oz. (twelve 5 oz. cups) coffeemaker”, while twelve 6 fl oz cups would be 72 fl oz, so the table gives both. Our page on how much ground coffee for 12 cups has the tablespoon counts and the other batch sizes.

How many grams of coffee beans per cup?

Weigh 9.8 g of beans for a 6 fl oz cup, or 13.0 g for an 8 fl oz mug. Those figures come from the Specialty Coffee Association’s standard brew ratio. Section 7.1.5 of SCA Standard 310-2021 reads: “The standard brew ratio of 55 g of coffee per 1.000 kg of 17±3°C water shall be used for both batch sizes as per 7.1.1.” The SCA now offers this standard only to members, behind a login; the copy linked here is an SCA-branded PDF hosted by CoffeeGeek, and we’ve confirmed the quoted sentence appears in it. The SCA’s sample-preparation standard for cupping, SCA 102-2024, is still hosted on its own site and sets the dose at “8.25 g of coffee per 150 mL of vessel capacity”, which is the same 55 g per liter.

The working is short. A US fluid ounce is 29.57353 mL according to NIST, and SCA 102 treats a milliliter of water as 1 g, so 6 fl oz of water is 6 × 29.57353 = 177.4 g. At 55 g of coffee per 1,000 g of water, that takes 177.4 × 0.055 = 9.76 g, which we round to 9.8 g. The 8 fl oz mug holds 236.6 g of water and takes 13.0 g, and a 12 fl oz mug (or two 6 fl oz cups) takes 19.5 g. The ratio is usually written 1:18, but 55 g per kg is really 1:18.2, so we always compute from 55 g per kg and never from the rounded 1:18.

No scale? The Golden Ratio is the spoon version: “1 to 2 tablespoons of ground coffee for every 6 ounces of water”. Mr. Coffee’s manual puts a level tablespoon at 5 g, so that range is 5 to 10 g per 6 fl oz cup, and the SCA dose of 9.8 g sits at its strong end. The 5 g is one maker’s figure and a heaped spoon holds more, so treat a spoon as approximate.

For a stronger cup, use more coffee, not less. At the middle-case bean weight each gram is about 7.6 beans, so a dose 10 percent bigger adds about 7 beans to a 6 fl oz cup. The same rule scales any dose, since other brewing methods use other ratios.

How much does one coffee bean weigh?

Agronomists measure bean size as hundred-bean weight. Urugo, Tola, Kebede and Ogah (2024), published in Beverage Plant Research, weighed 100 beans from each of 20 green arabica samples from different Ethiopian growing areas, in triplicate on a 0.01 g balance. The hundred-bean weight ranged from 13.22 to 17.28 g, mean 15.49 ± 0.98 g. Divide by 100 and one green arabica bean weighs about 0.13 to 0.17 g, averaging 0.155 g.

Two other sources agree on the average. Nugroho, Basunanda and Suyadi (2016) grew eight arabica genotypes at two altitudes in Indonesia and found 12.3 to 17.7 g per 100 beans at 10 to 12 percent moisture, averaging 16.2 g at the higher site and 15.2 g at the lower. A 2013 review of green and roasted coffee quality by Bicho and colleagues gives about 0.15 g for a typical green arabica bean. That is 0.15 to 0.16 g in all three.

You buy roasted beans, and roasting removes weight, mostly water. The green coffee importer Royal Coffee puts the span this way: “Very light roasts, dropped at the beginning of the first crack, will likely lose only about 10% of their green weight, but roasts taken well past the second crack may lose as much as 25%.” Its worked example for roasters uses about 12% for a light roast, 15% for a medium and roughly 20% for a dark. A 2024 roasting study in Scientific Reports describes batches with roasting losses of 14 to 16 percent as “generally light to medium roast levels”.

Combine the two, assuming each bean loses the same share of its weight, and a roasted arabica bean weighs roughly 0.10 to 0.16 g:

• Heaviest bean, lightest roast: 0.1728 g green × 0.90 (10 percent lost) = 0.156 g.
• Middle case: 0.1549 g green × 0.85 (15 percent lost) = 0.132 g.
• Lightest bean, darkest roast: 0.1322 g green × 0.75 (25 percent lost) = 0.099 g.

Divide the dose by the bean: 9.76 ÷ 0.132 = 74, which we call about 75. Roast level alone moves the count by about a tenth. At the average bean size, the 12, 15 and 20 percent losses above give 72, 74 and 79 beans for a 6 fl oz cup, because a darker roast leaves lighter beans and so takes more of them to reach the same weight.

How many cups of coffee are in a pound or a 12 oz bag of beans?

Divide the bag by the dose.

These are totals before any waste, at the standard dose, and a stronger cup uses the bag faster. Across the bean sizes and roasts above, a pound holds roughly 2,900 to 4,600 beans.

Does the bean count change for robusta, peaberries or large beans?

Yes. Bean size moves the count more than roast level does, and it differs between species and between arabica varieties.

• Large arabica beans. Nugroho and colleagues also quote a textbook figure of 18 to 22 g per 100 arabica beans (Wintgens, 2004), above anything either study measured. We haven’t read the book, so we can’t say which varieties or moisture level it describes. If your beans really are that heavy, the same arithmetic at a 15 percent roast loss gives roughly 50 to 65 beans for a 6 fl oz cup, about 57 at 20 g.
• Robusta. A Brazilian study of 86 Coffea canephora clones, the species sold as robusta, averaged 16.31 g per 100 dried beans, with individual clones from 10.0 to 25.1 g. At the average and a 15 percent roast loss that is about 70 beans for a 6 fl oz cup, and the clone-to-clone spread alone covers about 46 to 115. The 2013 review above instead says the mass of green robusta beans “is typically higher relatively to Arabica”, about 0.21 g against 0.15 g, which would be about 55 beans. So the sources disagree: the review has robusta beans heavier than arabica, while the clone study’s average (0.163 g) sits close to the arabica figures. Treat 55 to 70 as indicative for a robusta-heavy blend. Our page on robusta coffee beans covers what robusta changes about the cup.
• Peaberries. A peaberry is a cherry that produced one round seed instead of the usual two. We found no bean weights for peaberry lots, so we don’t print a count for them. Our page on Kenyan coffee explains where the PB grade sits and why grade letters describe the bean rather than the cup.

So treat any single bean count, including ours, as a midpoint. The average green arabica bean is 0.15 to 0.16 g in the three arabica sources, but individual lots depart from that in both directions.

Should you count coffee beans or weigh them?

Weigh them. Counting is slower than weighing and less accurate, because the thing that matters is mass, and bean mass varies: the heaviest of the 20 Ethiopian samples had beans 31 percent heavier than the lightest, and the Indonesian averages spanned 44 percent. The SCA’s cupping standard doses each cup by weight, asking for “a scale with 0.1 g or higher accuracy”, and adds: “Because of the mean mass of a coffee bean, a tolerance of ±0.2 g in the final mass of coffee per cup shall be considered.” At the middle-case weight that tolerance is about one and a half beans.

Scoops are no better. The 2013 review above gives an apparent density of 0.6 to 0.7 g/cm³ for green arabica and robusta and says it can fall to 0.3 to 0.4 g/cm³ as roasting time increases, so a scoop of beans can hold fewer grams the longer the roast. Our page on coffee roast levels covers the same effect. If you have no scale, use the spoon version above and accept that it’s approximate; our page on coffee tools and accessories covers scales.

How to work out the count for your own beans

1. Count out 100 whole beans and weigh them. The Ethiopian study measured bean size the same way, weighing 100 beans per sample in triplicate. On a 0.1 g scale a hundred-bean weight of about 13 g is read to within 1 percent, whereas a single 0.13 g bean is barely above what the scale can resolve.
2. Divide by 100 to get the weight of one bean.
3. Divide your dose in grams by that. For example, if 100 of your beans weigh 13.2 g, one bean is 0.132 g and a 9.8 g dose is about 74 beans.

We haven’t counted or weighed beans on this site’s scale, so that example is arithmetic, not a measurement.

The dose isn’t the only lever. The NCA’s guide says that if your coffee “tastes bitter or sour: it may be ground too fine (over-extracted), so try a larger, coarser grind”, and that if it “tastes flat or watery: it may be ground too coarse (under-extracted), so try a smaller, finer grind”. Guides split on sourness, though: a Gear Patrol pour-over guide ties it to the opposite fault, saying “grounds that are too coarse result in under-extracted, sour coffee”. If a sour cup gets worse after you grind coarser, go finer instead. Water temperature works from the other side; see our page on the best temperature for French press coffee for the range with its source.

Corrections to earlier versions of this page

Earlier versions of this page got these points wrong or left them unsupported. Each is corrected above.

• An earlier version of this page said “the Specialty Coffee Association defines a cup as 8oz”. That was wrong: SCA Standard 310-2021 never defines a cup in ounces. It gives the brew ratio by mass, and the word “cup” appears in it only for vessels: “sample cup”, and “an oven safe support or cup”. The 6 fl oz coffee cup comes from the National Coffee Association’s Golden Ratio, not from the SCA.
• An earlier version of this page used a 1:16 ratio. That was wrong: the standard reference figure is 55 g of coffee per 1.000 kg of water, which is 1:18.2 and usually written 1:18.
• An earlier version of this page said 15 grams of coffee is “around 75 beans”. That was wrong: it implies a roasted bean weighing 0.2 g, which would need a green bean of 0.22 to 0.27 g before roasting, heavier than the 0.17 to 0.18 g at the top of the two arabica studies above. The count was roughly right only because the wrong cup size and the wrong bean mass canceled out.
• An earlier version of this page said robusta beans are “typically larger” than arabica. We removed that because we couldn’t source it, and the sources we have read since disagree on it (see the robusta note above), so it stays out.
• An earlier version of this page said, with no source, that a grind that is too coarse turns coffee “thin and sour”. Guides disagree here: the NCA’s, quoted above, puts sourness under a grind that is too fine, while a pour-over guide ties it to a grind that is too coarse. The page now quotes both.
• An earlier version of this page showed the working as 177 × 0.055 = 9.8 g. That was wrong as written: those two numbers multiply to 9.735. The water is 177.4 g before rounding, and 177.4 × 0.055 = 9.76 g, so 9.8 g stands.
• An earlier version of this page answered “can I reuse my coffee beans” in its FAQ by advising fresh grinding on an airplane, on the grounds that “the altitude can affect the taste perception”. We found no support for that claim and removed it.
• An earlier version of this page also said a 0.1 g kitchen scale costs less than a bag of specialty coffee, and that grind size and water temperature change the cup “far more than a handful of beans either way”. We could not find a source for either claim and removed both.