What Size Frame for an A3 Print?

What Size Frame for an A3 Print

Without a mat, buy a frame the same size as the print: frame sizes are the size of picture they hold, not the outside of the frame. With a mat, go up a size: frame size = print size + 2 × the mat border.

A3 (297 × 420 mm) is twice the size of A4 and a popular size for art prints and posters. With a mat it usually goes in a 40×50 cm frame, or a 50×70 cm frame for a wide gallery-style mat.

The mat opening is cut a little smaller than the print, about 3 mm on each side, so the mat holds it in place. Ready-made mats are usually cut this way; custom framers often cut tighter, about 3 mm (⅛ in) a side, which is what the frame size calculator uses, so its opening comes out slightly larger.

Inch Frames for an A3 Print

A3 is 11.7 × 16.5 in. In the US and Canada, frames come in inches. A 12×18 in frame is close in size but a different shape, so the print either floats with a gap or needs a mat.

• With a mat: a 16×20 in frame gives a border of about 2⅛ in at the sides and 1¾ in at the top and bottom (narrower top and bottom).
• With a mat: an 18×24 in frame gives a border of about 3⅛ in at the sides and 3¾ in at the top and bottom (deeper top and bottom).

Will My Photo Fit an A3 Frame?

The A3 shape is 1 : 1.41 (all A-sizes share it). A print only fits without cropping if its shape matches:

• Phone photo (3 : 4): loses about 6% off its short side.
• Camera photo (2 : 3): loses about 6% off its long side.
• Square photo: needs a square frame or a mat with a square opening.

To avoid cropping, order the print to match the frame, or have a mat cut to your photo's shape. The frame sizes chart lists which sizes share each shape.

How High to Hang an A3 Frame

Hang it with the center of the frame at eye level, about 145–153 cm (57–60 in) from the floor. The nail goes at the center height, plus half the frame's outside height, minus the hook drop (how far the wire or D-ring pulls up below the top edge).