What numbers are equal to 54 inch luggage?

26"x18"x10" & 25"x19"x10" are just two sets of numbers that work, I use these as I have two suitcases that meet these dimensions. There are several others as all brands have differences. Remember to measure the maximum dimensions of the case, handles, wheels etc. These are good sizes as , if you pack carefully, you can meet the 50 pound checked bag weight limit of most airlines.