How We Verify Data

This page exists because a reference site is only worth the method behind it. Anyone can publish a container dimensions table; what makes ours usable for load planning is that every number has a traceable origin, a date and a route to being corrected.

Two independent sources per data point. A figure enters the dataset when two sources that do not copy each other agree on it. For dimensions that means an ISO standard plus a carrier specification sheet; for owner prefixes it means the official BIC register plus a second reference — a carrier document or an industry directory. Where two credible sources disagree, we publish the range and say why, rather than picking the prettier number.

What never counts as a source. Wikipedia, Reddit, forum posts, marketplace listings and content farms are excluded, however plausible the figure looks. A source enters our citations registry only if a figure on this site actually rests on it — the registry is a record of what we used, not a reading list.

Tested, not assumed. Claims about behaviour get tested rather than inferred. The carrier trackers in our tracker study were opened in a real browser with a real container number to see what each one accepts; where we have not run the test, the result reads "not tested" instead of a guess. The same rule governs deep links: a link format is published only after it opened a tracking result.

Dates on the data, not just the page. Every prefix record carries the date it was verified, and the registry as a whole carries a verification date shown on each page that uses it. A page’s "updated" stamp changes when its content changes — we never bulk-refresh dates to look fresh, because a false freshness signal is a form of inaccuracy.

One dataset, rendered everywhere. Numbers are never typed into prose. Every table, diagram, calculator and downloadable file reads from the same machine-readable dataset, which is why a correction lands on every page at once and why the tables cannot silently drift from the data. That dataset is public: container specifications and carrier and prefix data, free to reuse with attribution.

Corrections are logged, not quietly patched. When we get something wrong we fix it and record it. Send the page URL, the statement you believe is wrong and the document that supports the correction to data@contsize.com; the correction policy and the log live on the about page.

What we cannot verify. Prices move weekly and vary by market, so price figures carry a date and a range and should be treated as orientation, not quotes. Tare weights vary by manufacturer and production year: when this site disagrees with the CSC plate on your specific container, the plate wins. Saying so is part of the method.