How we calculate our numbers

Every derived metric on this site is computed from the sourced core specification. Here is exactly how, so the numbers are checkable, and citable.

Our numbers

Every derived metric, formula by formula

Seats per metre

Formula: typical seats ÷ fuselage length

A density proxy you can compare across sizes. It is how the A380's double deck shows up in a single number, more seats per metre of fuselage than anything else flying.

Range per tonne

Formula: maximum range ÷ MTOW in tonnes

How far each tonne of maximum weight takes you. Smaller aircraft score dramatically higher, it is an honest way to see why the industry moved from quads to light twins.

Span-to-length ratio

Formula: wingspan ÷ fuselage length

A shape signature. Above 1.0 the wing is wider than the aircraft is long, rare, and the A380 is the only one here that does it.

Weight per metre

Formula: MTOW ÷ fuselage length

Range in hours

Formula: maximum range ÷ cruise speed

Weight per seat

Formula: MTOW ÷ typical seats

Caveats. Derived metrics use each family's flagship variant as specified in its table. Typical seating is the manufacturer's multi-class figure; real airline layouts vary. These are comparison tools, not operational data.

What the ✓ tick actually means

Operator fleet counts move constantly, and most aviation sites quietly present a stale number as fact. We do not. Every operator row on this site is one of two things, and we say which.

A row marked has been individually checked against a named, dated source, an airline filing, a manufacturer statement, or a maintained fleet record, and that source is listed at the bottom of the page. A row marked is an approximate snapshot: broadly right, good enough to reason about, and not something you should quote in a contract. Currently 7 of 264 operator rows carry a tick, and the flagship fleets, Emirates, Southwest, United, are among them. That number will only go up.

We would rather show you an honest ≈ than a confident lie.

Where the core data comes from

Core specifications are taken from manufacturer documents, Boeing and Airbus airport-planning manuals and technical pages, and type certificate data sheets, cited per row on every spec table. Operator fleet counts are approximate snapshots, marked with ≈ and a last-verified date, and re-checked against airline press material.

Where sources conflict, we say so on the page and cite both. If you spot an error, tell us, corrections are made visibly, not silently.