Plot the size of the largest container ship by year and the line looks like a staircase that suddenly reaches a landing: 11,000-odd TEU with Emma Mærsk in 2006, 18,270 with the first Triple-E in 2013, past 20,000 in 2017, past 24,000 in 2022 — and then, essentially, nothing. MSC Irina's 24,346 TEU record was set in 2023 and still stands; the six largest classes afloat are separated by fewer than 600 boxes. The staircase has stopped climbing. It is worth being precise about why.
The walls are geographic
Every megamax is almost exactly 400 metres long and 61.5 metres wide, and that is not a coincidence of taste. Suez transit geometry, berth lengths at the world's deep-sea hubs, and the outreach of the largest container cranes all converge on the same envelope. Going longer or wider does not make a better ship; it makes a ship that skips ports. So the last two decades of records were won inside the box — more tiers, better lashing, fuller hull forms — and that game has diminishing returns measured in dozens of TEU.
The economics bend before the steel does
Scale cuts cost per box at sea and raises it everywhere else. A 24,000 TEU call concentrates thousands of container moves into one port stay, straining cranes, yards, trucks and rail; the megaships made schedules more fragile, not less. Insurers price the concentration risk — one hull now carries a small city's worth of cargo value — and the Ever Given demonstrated what a single stuck megamax does to everyone else's supply chain. The industry's revealed preference since has been networks and reliability over raw size: alliances reorganised, and the order books filled with mid-size, dual-fuel tonnage instead of new record-chasers.
It has all happened before
The tanker fleet ran this exact experiment in the 1970s and left the results on the beach. Five ships exceeded half a million tonnes deadweight; you can read all five on this site. Pierre Guillaumat, the largest ship ever built by deadweight, drew 29 metres fully laden — too deep for Suez, Panama, the English Channel and nearly every port on Earth — and was scrapped at six years old. Batillus went at nine. Only Exxon's pair, which had a captive trade, worked out. Seawise Giant, the longest ship ever, spent her final years as a storage hulk. The half-million-tonne tanker was not defeated by engineering; it was defeated by geography and markets, and no one has attempted the size since.
The record boards on this site may now be describing endpoints, not waypoints: Seawise Giant's 458 metres, Pierre Guillaumat's 555,051 tonnes, and quite possibly MSC Irina's 24,346 TEU.
Could the curve restart? A dramatically wider Suez, a new generation of ports, or fuels that change the hull equation could all move the walls. But the honest reading of the order books is that the giants' race is over for now — and that the superlatives this site catalogues are settling into history rather than being rewritten each spring. Which, for a site that measures things, is its own kind of gift: the boards below may be the final standings.