Methodology

Sources

Every airline has a list of official domains (for example the airline's own website). A figure is accepted only if it comes from a page on one of those domains. Each source keeps its address, the date it was checked and the short original sentence the figures were read from. If an official page cannot be opened, the airline is not published and nothing is copied from another website.

Verification

New airlines are first added as drafts. A draft is not shown in the checker, the rankings or the airline pages. Before an airline is published, every source page is opened again and each stored value is compared with the current text of the page. The airline is marked verified only if every source opened and every value matches. 80 airlines are verified today; each page shows the date of its last check.

Figures as published

• Sizes and weights are stored exactly as the airline publishes them, in cm or inches, kg or lb.
• Conversions are exact (1 in = 2.54 cm, 1 lb = 0.45359237 kg) and only rounded for display, to one decimal.
• Some airlines publish only a total (length + width + height). The site then shows that total, not invented sides.
• A value the airline does not publish is shown as “Not published by the airline”, with the source link.
• Wheels and handles are marked as included only when the official text says so for that bag.

How the checker decides

Both your bag and the limit are sorted from the longest side to the shortest, then compared side by side, so the bag may be turned any way. A total limit is checked as well when the airline publishes one.

• Fits: at least 1.5 cm to spare on every side and on the total.
• Tight: within the limit, but with less than 1.5 cm to spare somewhere. A bag exactly at the limit is tight.
• Risky: soft bags only, over the limit by 1 cm or less on a single side (and on the total, if any). It is never shown as fitting.
• Too big: every other case.
• Weight: fits, tight (within 0.5 kg of the limit) or too heavy. A combined limit counts both bags together.

The checker runs entirely in your browser. Your measurements are never sent to a server.

Rankings

Rankings use each airline's standard economy fare only, so business class allowances do not distort them. Airlines are compared by the total size of the included cabin bag (length + width + height, capped by a total limit when there is one). Airlines whose standard fare has no included cabin bag with a published size are listed separately.

Unique pages

Airline texts are built from the data of each airline: comparisons, ranks and tests that only apply to that airline. An automatic check compares pages of the same kind; a page whose text is more than 45% similar to another, or that has fewer than 250 words of its own, is kept out of search engines until it is improved.

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