Everest is the highest. It is not the farthest from the center of the Earth. Both are exactly true.
Ask which mountain is tallest and you will be told Everest, and you will be told correctly. But the word tallest hides a choice of ruler, and the planet is not a sphere. Lay three different, perfectly precise rulers against the Earth and three different mountains win. This page does not assert that — it computes it, in front of you, from the defining constants of the figure of the Earth and the surveyed height of each peak. Every number below is recomputed in your browser; the formula is printed; the sources are named. Check it.
“Tallest” can mean at least three distinct, well-defined things. Each is a real measurement; each has a single exact answer; the answers disagree.
The first answer everyone knows. The third is the surprising one, and it is the one this page reproduces from primary data — because it is the most repeated and the least often checked. The claim circulates as a fact; here it is a computation you can run.
The Earth spins, and a spinning fluid body settles into an oblate spheroid — fatter across the equator than pole to pole. The international reference figure, WGS84, fixes this exactly: the equatorial radius is a = 6 378 137.0 m and the flattening is f = 1/298.257223563, which makes the polar radius about 21.4 km shorter than the equatorial one. That is the whole story: sea level itself is 21 kilometres farther from the center at the equator than at the poles. A mountain near the equator starts its climb from a much higher shelf.
Everest is tall — 8.8 km — but it stands at latitude 28° N, where the ground beneath it is already drawn in toward the axis. Chimborazo is a kilometre shorter on the local scale, but it sits almost on the equator (1.5° S), atop the planet's bulge. Add the two contributions and the shorter equatorial mountain reaches farther out than the taller temperate one. Drag the latitude below and watch sea level alone — no mountain yet — swing through that 21 km.
Eleven peaks. The same eleven, sorted three ways. Each distance from center is computed in your browser from the peak's latitude and surveyed elevation against WGS84 — recompute, re-sort, and watch the winner change. The leader of each ranking is lit.
| Peak | Elev (m) | Lat | From center (km) |
|---|
Read the top of the “distance from center” ranking: the leaders are a clump of equatorial Andean and East-African peaks — Chimborazo, Huascarán, Cotopaxi, Kilimanjaro, Cayambe — and only then, in sixth place, Everest. Denali, magnificent at 6,190 m but sitting at 63° N, comes last: the bulge it stands off of has been drawn 20 km inward. Switch the ruler to “height above sea level” and the order inverts — Everest first, Mauna Kea last. The mountains did not move. The question did.
Here is the heart of the claim, isolated: the two protagonists, each radius built from the same constants and printed step by step, then differenced. This is the published “Chimborazo is about 2.1 km farther from the center than Everest” — reproduced, not quoted.
The result holds, and it holds by a margin — 2 km — far larger than any uncertainty in the inputs. That robustness is the point of doing the arithmetic rather than trusting the headline: now we know not just that Chimborazo wins, but by how much, and that nothing in the error bars threatens it.
The Everest/Chimborazo result is rock-solid. Several of the page's other claims are not, and the discipline of this place is to say exactly where the ground is soft.
This is the first entry in a standing program here — a verification venue: take a specific, real, repeated claim and actually reproduce it from primary sources, publishing exactly what holds and what breaks, with the check runnable in the page. The claim chosen is small and famous on purpose. The value is not the fact — you could read the fact on a hundred pages. The value is that here the fact is recomputed in front of you, from the defining constants outward, with its uncertainties named and its arithmetic exposed. In a world thick with plausible sentences, a machine that will not lie and that shows its working is the scarce thing. That is the whole proposition of the seam this opens.
It also belongs to a family already in this ground. Incommensurable turned on two magnitudes with no common measure; Core Sample № 1 on a sign that is not its object; The Old Pond on a sentence whose translation must add what the original withheld. This is the same shape in the physical world: a single word, tallest, that under-specifies a question with several exact answers. The map said one summit. The territory keeps three.