Tool · ratio chart

Coffee ratio chart: cups to grams (1:15–1:18)

How many grams of coffee for 1, 4 or 12 cups? Two printable charts — one for an 8 fl oz US cup, one for a 5 fl oz coffeemaker “cup” — plus a small calculator for any other size.

Updated 2026-10-14 · sources listed at the end · print this page for a kitchen copy (the calculator and drawing are left off the printout)

Mini calculator

Cup size

ml per cup

Cups

Ratio 1 : 16

Coffee29.6 g

Water473 g

water = 236.6 ml × 2 = 473.2 g · coffee = 473.2 ÷ 16 = 29.6 g

1:16 = 62.5 g of coffee per liter — a little stronger than the SCA’s 55 g/L ± 10% band (49.5–60.5 g/L).

Pick a ratio and the matching column is highlighted in both charts below.

Chart A: 8 fl oz US cups

Chart A — US customary cup: 8 fl oz = 236.6 ml of water per cup. Water and coffee in grams (1 ml of water ≈ 1 g).

Cups	Water	1:15	1:16	1:17	1:18	55 g/L
1	237	15.8	14.8	13.9	13.1	13.0
2	473	31.5	29.6	27.8	26.3	26.0
3	710	47.3	44.4	41.8	39.4	39.0
4	946	63.1	59.1	55.7	52.6	52.1
5	1183	78.9	73.9	69.6	65.7	65.1
6	1420	94.6	88.7	83.5	78.9	78.1
8	1893	126.2	118.3	111.3	105.2	104.1
10	2366	157.7	147.9	139.2	131.4	130.1
12	2839	189.3	177.4	167.0	157.7	156.2

Chart B: 5 fl oz coffeemaker cups

Chart B — coffeemaker “cup”: 5 fl oz ≈ 147.9 ml of water per cup. Water and coffee in grams (1 ml of water ≈ 1 g).

Cups	Water	1:15	1:16	1:17	1:18	55 g/L
2	296	19.7	18.5	17.4	16.4	16.3
4	592	39.4	37.0	34.8	32.9	32.5
5	740	49.3	46.2	43.5	41.1	40.7
6	887	59.2	55.5	52.2	49.3	48.8
8	1183	78.9	74.0	69.6	65.7	65.1
10	1479	98.6	92.4	87.0	82.2	81.3
12	1775	118.3	110.9	104.4	98.6	97.6

Water is the amount you pour, by weight or volume. Coffee is ground coffee by weight. The 55 g/L column is the SCA reference (about 1:18.2). Values are calculated, not tasted, and rounded to 0.1 g.

Which “cup” these charts use

“Cup” means different volumes depending on who is counting, so each chart states its size in milliliters. The SCA’s brewing best practices give the ratio per liter and do not define a cup of brewed coffee; the closest SCA figure is its cupping (tasting) protocol, which sets 8.25 g of coffee per 150 ml of water as the mid-point of the Golden Cup recipes.

“Cup”	Water	Where it is used
US customary cup (Chart A)	8 fl oz = 236.6 ml	Measuring cups; half a US pint
US nutrition-label cup	240 ml	Defined in US law for food labels; NIST’s kitchen tables round the cup to 240 ml
Coffeemaker “cup” (Chart B)	5 fl oz ≈ 147.9 ml	US carafe markings: about 4 fl oz of brewed coffee made from 5 fl oz of water
“Coffee cup”	150 ml	Used in the US to specify coffeemaker sizes; same volume as the SCA cupping reference

The coffeemaker figures differ slightly by source: a “12-cup” US coffeemaker is described as making 57.6 fl oz of coffee, or 4.8 fl oz per “cup”. Machines vary, so fill your carafe to its 1-cup or 12-cup line once, weigh the water, and enter that per-cup amount in the calculator.

Coffeemaker cup — 5 fl oz ≈ 147.9 ml of water; 9.2 g of coffee at 1:16.
“Coffee cup” / SCA cupping reference — 150 ml; 9.4 g at 1:16 (the SCA cupping protocol itself uses 8.25 g).
US customary cup — 8 fl oz = 236.6 ml; 14.8 g at 1:16.
US nutrition-label cup — 240 ml; 15.0 g at 1:16.

Drawn by pourxlab.com for this page from the cup volumes in Wikipedia’s Cup (unit) article, NIST’s conversion tables and the SCA protocols page (sources 5, 6, 7 and 1). Column heights to scale by volume; doses calculated at 1:16.

The formula and its inputs

water (g) = ml per cup × cups (1 ml of water ≈ 1 g)
coffee (g) = water ÷ R (R = the “16” in 1:16)
grams per liter = 1000 ÷ R (1000 ÷ 18.2 ≈ 55 g/L)

Input	Value	Source
SCA Golden Cup ratio	55 g/L ± 10%	SCA Protocols & Best Practices; SCA Standard 310-2021 tests home brewers at 55 g per 1.000 kg of water
Common filter range	15–18 : 1	Wikipedia, Coffee preparation (“by mass”)
Norwegian standard	63 g/L	Wikipedia, Coffee preparation
US fluid ounce	29.57 ml	NIST approximate conversions
US customary cup	236.6 ml	Wikipedia, Cup (unit)
Water mass per ml	≈ 1 g	The gram was defined as the mass of 1 cm³ of water; Wikipedia, Gram

Reading the charts

Find your cup size. Measuring-cup cups use Chart A; carafe markings on a drip machine usually mean Chart B.
Pick a column. 1:15 is the strongest in the chart, 1:18 the lightest. 1:16 is a common middle starting point.
Weigh, don’t scoop. Put the brewer on a scale, add the coffee from the chart, then pour the water figure.
Taste and move one column. Too strong: go right (1:17, 1:18). Too weak: go left (1:15). If the cup is sour or bitter rather than weak or strong, adjust the grind instead.

Why 1:18 and 55 g/L are nearly the same

The SCA states its ratio per liter, not as 1:x. Dividing 1000 by 55 gives about 1:18.2, and the ±10% allowance (49.5–60.5 g/L) runs from just over 1:16.5 (1000 ÷ 60.5 ≈ 16.53) to about 1:20.2 (1000 ÷ 49.5). That is why the 1:18 and 55 g/L columns are within a few tenths of a gram, and why the 1:15 and 1:16 columns — which many recipes use — sit on the stronger side of the SCA band. SCA Standard 310-2021 pairs its 55 g/kg test ratio with a target strength of 1.15–1.55% dissolved solids, measured with a refractometer; the extraction yield calculator turns such a reading into an extraction percentage.

The charts do not tell you which ratio tastes best. Taste research is moving on: UC Davis Coffee Center work, supported by the SCA and the Coffee Science Foundation, fed into a new Sensory and Consumer Brewing Control Chart announced in January 2025. It updates the 1957 chart associated with Ernest E. Lockhart, first director of the Coffee Brewing Institute. As UC Davis’s William Ristenpart explains in the university’s write-up, a scale plus your coffee-to-water ratio, grind size and brew time together indicate the flavors to expect — so treat the chart as a starting point and taste.

Common questions

How many grams of coffee per cup?

For an 8 fl oz cup of water: 15.8 g at 1:15, 14.8 g at 1:16, 13.9 g at 1:17, 13.1 g at 1:18 and 13.0 g at 55 g/L. For a 5 fl oz coffeemaker cup (147.9 ml) at 1:16: 147.9 ÷ 16 ≈ 9.2 g.

Why does the pot hold less than I poured?

The ratio is measured on the water you pour. Wet grounds keep some of it, so the brewed coffee weighs less than the water column. More on this in the coffee-to-water ratio guide.

Does this work for espresso, moka or cold brew?

No. Those methods use very different ratios — see the espresso ratio, moka pot and cold brew guides. These charts are for filter, drip and French press style brewing.