Personal Item Size Checker by Airline
Check whether a packed underseat bag fits a published size box. If the airline gives no fixed dimensions, you’ll see that instead of a guessed result.
The underseat item is a different bag category from an overhead carry-on. Start with its packed dimensions and the airline actually flying your trip.
These tools help you plan. They don’t take payment or decide whether an airline will accept a bag. When a price or limit is missing, check it with the airline.
After you get a result
Compare it with your ticket, the airline flying each leg, and the final price in its booking flow. If you’re flying round trip, check both directions.
What this tool can tell you
Your personal item needs to fit under the seat and within any size box the airline publishes. Some airlines say only that it must fit, without giving one inch-by-inch limit. In those cases, this tool won’t invent a pass or fail.
Try an example
Try an 18 × 14 × 8 inch bag with American or Frontier. Then choose Delta: its published page describes underseat fit, but we haven’t confirmed one universal numerical box there.
Open the airline link in your result before you pay. You don’t need to enter a booking number, passport, or payment details here.