Why does coffee have its own fluid volume measurement?

This is nuts!

I have long not trusted the 'cups' on the side of my coffee machine, so this morning I decided to drink my coffee out of a Pyrex measuring cup rather than a mug. I made 6 'cups' of coffee, and I have gathered 24oz of coffee exactly. 4 oz of coffee = 1 cup of coffee? Nonsense! (1 cup of any other fluid is 8 oz).

I have also read in the past that a cup of coffee is often considered 6 oz of coffee. WTB? (what the berkely)

Wait til Starbucks takes over more of the world and the carafe is marked "Short, Tall, Grande" etc...

4oz and 6oz seem berserk. Why a smaller cup than an actual cup, which is a rather small cup when it comes to coffee?

 The 6 oz cup mentioned on coffee cans has always bothered me.  That's like a 12 oz pound.... well you get my point.

See also: drivemaker's kilobytes. The bigger the drives get, the more wrong their capacities are in absolute units. I have a "4TB" drive in my home server that is actually 3.6TB because drivemakers wilfully use an inaccurate decimal approximation of a small binary unit. So this drive is 400 berkeleying gigs smaller than it says on the tin now. I have whole drives in my gaming PC that aren't that big. When will this madness end?

Yup. I just ignore those 'cup' measurements. Once my wife was like 'you drank 10 cups of coffee' this morning. I was like 'yeah, it's only three mugs worth.'

I'm beginning to see how napoleon drank 20+ cups of coffee per day. If that's only 80 oz he was way better off than the 3-4 24oz diet mtn dew crowd.

I'll ask our Canadian friends how this is handled in the metric world?   Does you coffee pot say cups (and possibly coupe too for French)?  

I'm presuming that cup (of coffee) is not intended to mean cup (imperial measurement, 8oz)

I was aware that there was a discrepancy but since working from home, I had to know now...

So, I just filled my 12 cup coffee pot and then poured that liquid into an imperial graduated cylinder (Pyrex) and 12 cup of coffee yielded 7 cups or 56oz.    Strangely, 56oz divided by 12 is 4.67 per cup of coffee (I had no spillage)  

In reply to RossD :

I was once asked by my doctor how much coffee I drank in the morning.

Me: "What do the numbers on the side of the carafe mean?"

Her: "Those are cups"

Me: "Then 12 if I'm having a good morning 18 if its a bad one. But it fits into 3 of my cups."

I'm pretty sure she wondered how I was still alive every time she saw me.

Interesting on the Canada angle. So I went to TheBay.ca to shop coffee makers.  Look what I find...

Zoom in to this listing and though 12 is referenced the word cup is not there on the pot.  Instead, water and coffee (which are not the same and must assume loss to steam)

The description of this KitchenAid admits it is a 8 cup model with each cup being 5oz.  The use of ounces strikes me as odd in a country that requires metric.  

The grounds absorb quite a bit of water. If I fill up the tank to 10 cups, I seem to only get 8 in the carafe.

I'm actually thinking of replacing my drip machine that has the bean grinder right in the basket with one that is above the basket so that I can still have fresh ground beans and filtered coffee. I saw one at a department store but I just don't need to replace my machine yet...

Robbie said:

I'm beginning to see how napoleon drank 20+ cups of coffee per day. If that's only 80 oz he was way better off than the 3-4 24oz diet mtn dew crowd.

Wait a minute. People actually drink DIET MTN DEW!? WTF is wrong with those people?

I don't drink cups, I drink about 3 PPD.

Pots

Per

Day

Paul

In reply to Nick Comstock :

I switched to diet Mountain Dew. 

The stuff tastes awful, but it has the same caffeine level, so a similar kick without the sugar. I lost 15 lbs pretty quickly with no other changes in my diet or routine. 

I used to own a coffee shop. 

I got nothin'. 

Besides cups not being cups, mine has a scale on the carafe and a different scale in the water reservoir. The one in the reservoir accounts for water that stays in filter/grounds. So I fill my carafe to 11 'cups', pour it into the machine,and get 10 'cups' out that ends up being three mug fulls. 

This is probably the most thorough discussion I was able to find in two minutes:

https://www.jesrestaurantequipment.com/howcoffeecarafesizingworks

"To understand the seeming discrepancy here, just remember that the word cup can mean a few different things and, keep in mind, that there are people in this world called “Advertising Executives” who are very skilled at twisting words around. When used to compare the volumes of unlike things, the word cup usually means “eight liquid ounces,” but cup can also refer to something else: the white, ceramic, World’s-Greatest-Dad-type mug that people drink their coffee out of.

Several decades ago an advertising agency decided that their coffeemaker client should start listing coffee pot capacities by this World’s-Greatest-Dad definition of cup instead of by the more apt, unit-of-measurement sense of the word. Now, as you know, mugs — cups — come in all different sizes, and who’s to say how much liquid the average coffee cup holds? This trail-blazing advertising firm thought deeply about this question and decided that the average cup of coffee is equal to exactly five ounces, or three-fifths of an imperial cup, a 40% decrease in size. Soon the rest of the coffeemaker industry listed its pot capacities by this new World’s-Greatest-Dad cup measurement instead of by the old — half-a-millennium old — measurement. They did this, surely, to make things more convenient for the customer."

spin_out said:

 The 6 oz cup mentioned on coffee cans has always bothered me.  That's like a 12 oz pound.... well you get my point.

 

Otherwise known as a "Troy pound".

Appleseed said:

Because most coffee drinkers are shiny happy people. 

Marked as no value, inflammatory, or spam!

Nick Comstock said:

Robbie said:

I'm beginning to see how napoleon drank 20+ cups of coffee per day. If that's only 80 oz he was way better off than the 3-4 24oz diet mtn dew crowd.

Wait a minute. People actually drink DIET MTN DEW!? WTF is wrong with those people?

Im down to a single 2 liter of diet mt dew a day. 

I used to drink 3 a day. After i gave up my 2 gallon a day coffee habit. 

Yes, i had a heart attack at 36.

I'm not actually sure what's worse for me, the two energy drinks in the morning when I'm working or my coffee when I'm not.


Seeing as my coffee recently had to be made weaker as I was giving myself constant heartburn drinking it, and it's still stronger than anyone I know aside from my mother drinks, I'm leaning towards the coffee.


Also, fun fact. Using budget energy drinks to brew coffee? Works. I know, I tried it once. 

I felt like I was going to die but I was berkeleying AWAKE 

In reply to Dusterbd13 :

I can understand MTN Dew that stuff is the nectar of the Gods. But diet is brewed in Hades. 

I had to quit MTN Dew twelve years ago because my boys weren't swimming straight and the little pokey doctor said it was the MTN Dew that was doing it. I still sneak a couple in here and there though. 

I don't drink coffee. Mainly water.

In reply to Robbie :

Was it espresso in tiny cups back then?

Robbie said:

1 cup of any other fluid is 8 oz

Maybe for a US customary cup in US customary fluid oz. But if using a US legal cup it's 240ml (8.12 US customary fluid oz), or the Canadian cup it's 8 imperial fluid oz (7.69 US customary fluid oz)...Or any of the various metric based cups throughout the rest of the world, that most commonly seem to use either 200ml (6.76 US customary fluid oz) or 250ml (8.45 US customary fluid oz).   Because consistency.

It's like asking "What is the airspeed velocity of an unladen swallow?"...African or European?

However, I'd guess the main reason for the difference between a US customary cup and a US (or any other)  'cup of coffee', is that the former is a technical unit of measure while the latter is based on a 'serving size'.  Much like a 'glass of wine' as a serving size is still 150ml (0.634 US customary cups, or 5.07 US customary fluid oz), even if one (comically large) wine glass allows me to drink it a half a bottle (or more) at a time..

Appleseed said:

Because most coffee drinkers are shiny happy people. 

Hey, I resemble that.