(updated August 25th, 2026)
The difference is foam, not ratio. A cappuccino is a single shot of espresso under a thick cap of foam, a centimetre or two of it. A flat white is usually a double shot in a cup of much the same size, finished with barely any foam at all. More coffee, less froth, and you taste that from the first sip.
You’ll often see the two set apart by ratio, with a cappuccino described as equal parts espresso, steamed milk and foam. That isn’t what separates them, and it isn’t how either drink is specified. What actually differs is how much air goes into the milk, and how many shots sit underneath it.
How Much Foam Does Each Drink Have?
This is the difference that does the work, and there are numbers behind it. Carmen Clemente, the 2022 World Latte Art Champion, told Perfect Daily Grind that “the cappuccino requires at least 1cm of microfoam”. The same article puts a flat white’s layer at no more than 0.5 cm. Melissa Caia, who runs the William Angliss Institute’s Coffee Academy, gave the teaching standard to the Sydney Morning Herald: “We say two centimetres for a cappuccino, one centimetre for a caffe latte, and minimal foam on a flat white.”
The foam is a different substance in each cup, too. On a cappuccino it sits on top as its own layer, which is why the first mouthful is mostly air and sweetness before the coffee arrives. On a flat white the air is worked all the way through the milk, so there’s no cap to get past and the coffee is there immediately.
That changes how each one drinks down. A cappuccino shifts as you go, foam first and coffee later, so the last mouthful isn’t much like the first. A flat white doesn’t shift at all. If you like a drink that stays put, that’s the one.
Side by side, with the foam figures from Clemente and Caia:
| Cappuccino | Flat white | |
|---|---|---|
| Espresso | Single shot | Usually a double |
| Foam | 1 to 2 cm, sitting on top | No more than 0.5 cm, worked through the milk |
| Cup | 150 to 180 ml (5 to 6 oz) | Much the same |
| First sip | Foam, then coffee | Coffee straight away |
Neither drink’s tightly standardised outside Italy, and cafes vary, so read that as the shape of each drink rather than a rule anyone is enforcing. It is worth knowing where the equal-thirds idea came from, though, because it was never either drink’s specification. Craig Dickson, a World Barista Championship judge, told the Herald in 2015: “I have seen some old chain-store training material that suggests the third-third-third ratio, but it has never been part of the WBC rules.”
Which One Is Stronger?
The flat white, on both counts. It carries more caffeine because it’s built on two shots rather than one. USDA FoodData Central puts a 1 fl oz shot of espresso at 62.8 mg, so a single-shot cappuccino lands near 63 mg and a double-shot flat white near 126 mg. I’ve gone through how many shots go in a cappuccino separately.
It also tastes stronger, which is a separate thing from the caffeine. There’s less milk diluting the coffee and no foam layer softening the opening. A cappuccino’s foam brings a sweetness of its own, and that’s part of why the same espresso reads milder in one cup than the other.
Are They Served In The Same Size Cup?
Broadly yes. Both sit around 150 to 180 ml, which is 5 to 6 oz, so the flat white fits double the espresso into the same volume. That’s the whole reason it drinks as the more coffee-forward of the two. There’s more on what size cappuccino cups are in ounces.
The cups often look different even at the same capacity. A flat white tends to arrive in something wider and shallower that shows off the flat milk surface, a cappuccino in something deeper that gives the foam somewhere to sit. That’s convention rather than specification, and plenty of cafes use the same cup for both.
Where Did The Flat White Come From?
The cappuccino is Italian and well documented. The flat white is much younger and its origin is disputed, with claims from both Australia and New Zealand. Australian Geographic makes the case for Sydney: cafe owner Alan Preston put “flat white” on the menu at Moors Espresso Bar in Chinatown in 1985 and documented it in photographs. Preston says he brought the drink down from Far North Queensland, where cafes had been serving it to Italian sugar-farming families.
New Zealand’s claim hasn’t gone away, and the debate is still running. What isn’t disputed is what the drink is for: less foam, more coffee, and a milk texture that stays the same from the top of the cup to the bottom.
Which Should You Order?
Order the flat white if you want the coffee to lead: two shots, no foam layer, the same texture from first sip to last. Order the cappuccino if you want the foam to be part of the drink, with a lighter, sweeter opening before the espresso comes through.
If you’re stuck between them, the useful question isn’t which is better. It’s whether you want the milk to carry air. Everything else about these two drinks follows from that one decision.
