Picture Frame Mat Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 27, 2026Sizing a mat for custom framing
A mat's overall size is simply the artwork or photo dimensions plus a border on all sides - getting this calculation right before cutting mat board (or ordering custom-cut mats) avoids wasted material and mismatched frame sizes.
Worked example
For an 8x10 inch photo with a 2-inch border:
Mat Width = 8 + (2 x 2) = 12 in
Mat Height = 10 + (2 x 2) = 12 in x 14 in overall
Professional framers often make the bottom border slightly wider than the other three (about 25% more) - a mat with perfectly equal borders on all sides can create an optical illusion of the image sitting too low, so a wider bottom border corrects for this.