To measure your luggage bag or suitcase, first stand it upright (with wheels on the bottom for rolling luggage) and the extension handle on top. Begin measuring your travel luggage from the bottom of the wheels or travel bag all the way to the tallest part (without the handle extended). This is the height of your luggage and is the measurement that is most important for carry-on luggage.
Next, lay your travel luggage on its side and measure the width from side to side at the widest part. This is most likely the middle of the back of a soft-sided suitcase. Generally speaking, hard shell luggage is symmetrical and you won’t have to worry about the width varying from top to bottom.
Finally, it’s time to measure your travel bag, suitcase, or luggage depth. To get an accurate measurement of the depth of your luggage, lay it flat on its back. Then, measure from the front to the back without expanding the bag to ensure the correct measurement.
Depending on the style of your travel luggage and amount of items packed, this measurement can vary widely. Soft-side luggage that is stuffed full will have a much different depth measurement than when in its unpacked form. Similar to the height, the depth measurement is critical for carry-on luggage because the travel bag must fit into the aircraft’s overhead compartments.