Data Methodology
How We Collect Data
Every airline record on CarrySizer is sourced directly from official airline websites and their published fare rules. We do not rely on aggregators, crowdsourced submissions, or third-party data vendors for our primary figures. Each entry links back to the specific page or document we used so you can verify it yourself.
Primary sources include airline carry-on policy pages, fare conditions PDFs, checked-baggage fee schedules, and — where available — official customer service confirmation via the airline's help center. When official sources conflict (for example, a website says one dimension and a fare PDF says another), we use the more conservative figure and flag the discrepancy in our notes.
What We Check
For each airline and cabin class combination, we record:
- Carry-on dimensions— length, width, and depth in centimetres, plus the linear sum (L+W+D).
- Weight limit— maximum carry-on weight in kilograms where the airline specifies one.
- Personal item— whether a personal item (handbag, laptop bag, backpack) is permitted in addition to the carry-on, plus its size and weight limits.
- Gate-check fees— the fee charged when a carry-on is rejected at the gate and must be checked, where published.
- Cabin enforcement notes— whether the airline is known to enforce size limits strictly, spot-check only, or rarely enforce.
Quality Gate Criteria
An airline entry must pass our internal quality gate before it appears on the site. All four of the following must be true:
Cabin dimensions required
All three measurements (length, width, depth) must be present. Entries that only list a linear total are not published because they cannot support accurate bag-fit calculations.
Personal item flag required
The entry must explicitly state whether a personal item is included. We do not assume either way.
Source URL required
Every entry must have a direct link to the official source page. Entries without a verifiable source are held in draft until a source is confirmed.
Last checked within 12 months
Each record carries a last_checked date. Entries older than 12 months are automatically marked stale and excluded from featured placement until reverified.
Freshness Levels
We classify each airline entry's freshness based on itslast_checkeddate:
Checked within the last 6 months. Displayed without any warning.
6–12 months old. Displayed with a note suggesting you confirm with the airline.
Over 12 months old. Flagged prominently and queued for immediate reverification.
Disclaimer: Airline baggage policies change without notice. CarrySizer makes every effort to keep data accurate and current, but we cannot guarantee that the information displayed matches your specific booking, itinerary, or fare class. Always confirm carry-on rules directly with your airline before travel. We accept no liability for fees or denied boarding resulting from reliance on this data.
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