Use the bag price, net weight, and dose to get the bean cost of one homemade cup. The default is a 12 oz (340 g) bag at $18 with 15 g per cup, about 22.7 cups at $0.79 each. That is bean cost, not a cafe comparison.
Updated: Sep 2, 2026Reviewed by: Content and layout review
What this calculator does
If you buy a bag and brew at home, average bean cost per cup is:
bag price × dose ÷ bag weight
The default is a 12 oz (340 g) bag at $18 and 15 g per cup: about 22.7 cups at $0.79 each. Fifteen grams is the same filter starting point as brew ratio and the brew ratio calculator. It is not a required cup size.
Use the net weight printed on the bag. For help understanding the other label information, see how to read a coffee bag; for care after opening, see storing coffee.
How to use it
Enter what you paid, the grams on the bag, and the dose you actually use. The buttons—½ lb, 1 lb, 250 g, 12 oz, and 1 kg—only save typing; they do not mean a size is a better deal.
The estimated number of servings is the bag’s net weight divided by the dose per cup.
Where the numbers come from
The 15 g dose matches the site’s usual 1:16 filter start. The 12 oz default follows a common North American retail size. A half pound is 227 g and a pound is 454 g on this page, from avoirdupois ounces rounded to whole grams; 250 g is widely cited as a global specialty retail size. These are common packaging sizes; use the net weight printed on your bag.
The default price is not a market survey and not a suggested retail price.
What the number cannot tell you
This page does not add filters, water, power, milk, or time, and it does not amortize a grinder or kettle. It cannot tell you that home brewing is cheaper than a cafe, and it cannot tell you whether the coffee tastes good.
Common Misconceptions
Is $18 a typical bag price?
No. It is an example value you can replace. Use the price on your bag or receipt.
Why 15 grams per cup?
It matches the site’s brew-ratio calculator—15 g of coffee to 240 g of water, a common 1:16 filter start. For espresso or another recipe, enter the dose you actually use.
Why default to 12 ounces?
It has long been a familiar North American retail size, about 340 g. Buttons also cover a half pound (227 g), 1 lb (454 g), 250 g, and 1 kg. Use the net weight on the package.
What if the last brew does not fill a full dose?
The result is the cost of one serving at your selected dose. A final brew using fewer grams costs less. A fractional cup count represents equivalent full-dose servings, not the number of times you brew.
Does this include filters, electricity, or a grinder?
No. It is roasted-coffee cost only. It is not a cafe-versus-home comparison; a shop price also covers rent, labor, and often milk.
SCAA Standard, Golden Cup, revised 23 December 2015: The standard provides a filter-brewing reference of 55 g of coffee per liter of water. This calculator uses the same 15 g starting dose as the site’s brew-ratio calculator; prices are entered by the user and do not come from the Golden Cup standard.
MTPak Coffee, Is the standard coffee packaging size changing?, 2026: Industry packaging overview: 250 g is a widely recognized specialty retail size globally; North America long used 12 oz (about 340 g) bags. There is no single standard, and some roasters have moved toward 200 g or 300 g. The English default uses 12 oz as a common U.S. retail size, not a price survey. Half-pound and 1 lb buttons use the same avoirdupois weights.
NIST Special Publication 811, Guide to the SI, Appendix B.8: 1 avoirdupois ounce = 28.349523125 g. 8 oz (half pound) is about 226.80 g, rounded to 227 g. 1 lb is about 453.59 g, rounded to 454 g. 12 oz is about 340.19 g, rounded to 340 g.