Ask what a Boeing 777-300ER's cabin looks like and you have not asked a question yet. Across the researched layouts published on this site, that one airframe flies with as few as 212 seats and as many as 472. The walls are identical. Everything between them is an airline's commercial decision.
In short
The same aircraft type can differ by hundreds of seats between airlines. Across the 454 published cabin layouts, the widest spread on one type is 260 seats on the Boeing 777-300ER, displayed economy pitch runs from 28 to 33 inches, and 11 aircraft types show a spread of more than 100 seats between their operators. A seat map is only accurate when it is drawn for the airline flying the aircraft, not for the type.
One airframe, two very different aircraft
All Nippon Airways configures the Boeing 777-300ER with 212 seats, giving most of the cabin to premium classes. Air France's densest researched configuration of the same type carries 472. A traveller who has flown one would not recognise the other from the inside, and a seat map drawn for either one misdescribes the other in nearly every row.
The pattern is not a widebody quirk. Of the 28 researched aircraft types flown by two or more airlines, 11 show a spread of more than 100 seats between their smallest and largest configuration.
| Category | Fewest seats | Most seats |
|---|---|---|
| 777-300ER | 212 | 472 |
| A350-900 | 161 | 391 |
| A380-800 | 407 | 615 |
| A350-1000 | 213 | 397 |
| 787-8 | 184 | 335 |
| A330-300 | 226 | 363 |
The extremes have stories the data states plainly. Singapore Airlines' smallest researched Airbus A350-900 configuration carries 161 seats and no economy cabin at all: 67 in business and 94 in premium economy. Emirates' densest Airbus A380-800 carries 615 across two classes, while Korean Air configures the same double decker with 407.
Pitch varies as much as the seat count
Seat count is the visible half of density. The other half is seat pitch, and across the 167 economy cabins where the pages display one, it runs from 28 inches on Austrian Airlines' Airbus A320neo to 33 inches on Philippine Airlines' Boeing 777-300ER. Five inches is the difference between a laptop that opens and one that does not, on two seats that both sell as economy.
The pages display a pitch on 230 of the 977 cabins in the published layouts, because a pitch is shown only where it is recorded with confidence. Where it is not, the pages say "not recorded" rather than estimating, and this article holds itself to the pages' own gate: a figure the reader cannot see on the linked page does not appear here either.
What this means for anyone selling a seat
A seat map keyed to the aircraft type is wrong somewhere for 11 of the types above, and can be wrong by an entire cabin class. The researched layouts behind this article are published as browsable seat maps for every airline and aircraft pairing, and the seat selection product draws the cabin for the operating airline of the actual flight, which is the only version of the map that answers the traveller's real question: what is this seat, on this aircraft, on my booking?
Frequently asked questions
Why does the same aircraft type have different seat maps?
Because the airframe fixes the walls and the airline chooses everything inside them. Cabin classes, seat models, galley positions and pitch are commercial decisions, so two airlines can configure the same aircraft type with hundreds of seats between them.
How different can two airlines' versions of one aircraft be?
In the researched data, the widest gap on one type is 260 seats: the Boeing 777-300ER flies with 212 seats in its most premium researched configuration and 472 in its densest.
Does a generic seat map for an aircraft type mislead travellers?
Often, yes. A generic map shows one configuration of a type that may fly in a dozen. The row that map shows as standard economy can be an exit row, a different cabin, or missing entirely on the aircraft actually scheduled.
Where do these figures come from?
From the cabin layouts published on this site, through the same publication filters the seat map pages use: every figure is computed from the same data that renders those pages, and a test recomputes each one whenever the data changes.