How to measure photo frame size

To measure a photo frame size, measure the dimensions of the frame opening (where the photo or artwork sits), not the outer edge dimensions of the frame itself, since frame size conventionally refers to the picture it holds, not the frame's total outer measurements. Use a ruler or tape measure to measure the width (horizontal) and height (vertical) of the opening in inches or centimeters, recording as width × height (for example, 8×10 inches).

Understanding frame measurement conventions prevents purchasing mistakes. When a frame is labeled "8×10," this means it holds an 8-inch wide by 10-inch tall photo—the outer dimensions of the frame will be larger due to the frame's border width. To measure a frame you already own, measure the glass size or mat opening (where the photo shows through), not the rabbet (the recessed ledge where the glass sits), which is slightly larger to hold the glass and backing. If replacing glass or matting, measure the rabbet depth and width carefully. Standard frame sizes in inches include 4×6, 5×7, 8×10, 11×14, 16×20, and 18×24, though many other sizes exist. Custom frames accommodate non-standard sizes but cost more than standard sizes. When buying frames online, carefully check whether listed dimensions refer to frame size (picture opening) or outer dimensions—reputable sellers specify "holds 8×10 photo" or "8×10 frame size." For matted photos, the frame size must accommodate both the photo and mat border—an 8×10 photo with a 3-inch mat border all around needs a 14×16 frame. Always measure twice before purchasing, especially for custom printing or framing, to ensure your photo fits properly without gaps or requiring trimming.