The exact measurements of this backpack are 22 cm in length, 38 cm in width, and 42 cm in height. These dimensions are slightly larger than the typical carry-on bag size limit of 40 cm x 20 cm x 25 cm, so it might not fit within those specific constraints. However, it is designed as an expandable carry-on, which could potentially allow it to be compressed to fit within those limits, depending on how it is packed.