Marilyn Bohn, of Get it Together Organizing, offers a travel tip of how to measure carry on luggage. She warns you that every carrier has a different requirement for carry on luggage, so check before you leave what your carrier requires. In order to measure your carry on luggage you use three different figures and add them together for the final result. Measure length, measure width, and measure depth. Write your numbers down and then add them together. After this, you will come up with a single number, call your carrier, ask them if they allow this and if so, you have properly measured and can take your carry on bag with you! Enjoy your trip!