Sources and review method
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Sources
Every rule on this site comes from an official source: the TSA for security screening, the FAA for dangerous goods, and each airline's own pages for its policy. Each rule links to the page it was taken from. A rule without a source is never published. We do not copy the sources in full; we summarise the conditions and link to the original.
How a rule is reviewed
- AI reads the official source. An AI model reads the text of the official page and drafts a structured rule: the item, whether it is for carry-on or checked bags, the result, and each limit with the exact wording it comes from. Every number in a draft must appear in the quoted source text, and each limit must match how the source words it ("up to", "more than" and so on). Drafts that fail these checks are not kept.
- A second, separate reading. A second AI reading, done separately and without seeing the first draft, reads the same source again. The two readings are compared item by item: the result and every limit must be the same. Any difference is flagged for a person to look at.
- The operator approves. The site operator compares the rule with the source and approves it. Only approved rules are published. Rules where the two readings disagree are reviewed one by one.
Where a source does not mention a case, or we could not read the source, the rule is left out and the result is "we can't confirm this yet" rather than a guess.
Units and numbers
- Limits are stored in the units the source uses. If the source gives the same limit in two units (for example inches and centimetres), both are kept as written, and meeting either one counts.
- Conversions between units use exact definitions and are not rounded when comparing.
- For batteries, the Wh rating printed on the battery is used first. If only mAh is given, the rated voltage is needed: the site never assumes a voltage.
Review dates
Each rule shows the date it was last reviewed. Battery rules are rechecked weekly and other rules monthly, and an official change notice is checked as soon as it is found. A rule that passes its review date without being rechecked is no longer used for results and is shown as "Being rechecked". Rules can still change between reviews, so check the official source before you travel.
How results combine
Security screening, dangerous goods and airline rules all have to be met. If any of them rules an item out, the result is "Not allowed". If any of them cannot be confirmed, the result says which part is missing. Limits from different rules are listed separately with their sources, never merged into one number.
All published changes are listed on the rule changes page. To report a mistake, see corrections.