Wingspan is simply finger tip to finger tip measurement. Now I'v read its usually matches your height or a little bigger. I only ask because as a person interested in Boxing I am trying to figure out if I can match people in my height class, I obviously can't ask for weight that is rude.
I am 5'8.6" with a 69" wingspan, my arm length is 26".
Feel free to add arm length too, simply measurement of armpit to end of fist. Don't worry about putting the metric system, I can easily convert.