How big of a snowboard?

If your going to buy one, the shop should know the right size for you but this website will calculate it for you, you just gotta put your height, weight, and ability: http://www.snowboardlengthcalculator.com/

I'm 5'3" and use a 135. Make sure the snowboard, when standing up, is somewhere around your face.

I agree to use: http://www.snowboardlengthcalculator.com/ Your weight plays a part due to the displacement of the board on the snow so you don't dig in but your height also comes into factor for turning if the board is too short and your center of gravity is too high then you will fall over I have put your details into the site and have made a guess at your weight but you can do this your self and have come out with. 149 but you could probably go up to 152 and not have any problems But also consider going to the snowboard asylum situated in places like xcape where they have test boards you can try (i.e. try before you buy) which can help you find the style of board you like. The link is below and tells you where they are situated and can give you more advice on the matter http://www.snowboard-asylum.com/demo.htm

the board should be between your chin and nose when you stand it up in front of you. Its 2.54 cm to an inch so measure to your mouth with a tape measure and do the math. Its always a good idea to go a little big if you think you're still growing but keep in mind if your going to be using the board in icy conditions your going to get much more speed than you would like.