on June 04, 2026
An A4 print is 21x29.7cm. That's the answer to the first part of the question. What size frame you need depends on how you intend to display it.
Framing an A4 Print Without a Mat
If you're framing the A4 print directly — no mat, the print fills the frame — you need a frame with an inner opening of exactly 21x29.7cm. Buy a frame labelled A4, not a frame labelled 20x30cm — the dimensions are close but not identical, and the print will either not fit or sit loosely in a 20x30cm frame.
ONE MAAY's picture frames include A4-specific options designed for this exact fit.
Framing an A4 Print With a Mat
If you want a mat border — which adds visual breathing room and prevents the print touching the glass — you need a larger frame. The frame size depends on the width of mat border you want:
Narrow mat (3cm each side): Frame inner opening approximately 27x36cm — use a 30x40cm frame with a custom-cut mat.
Standard mat (5cm each side): Frame inner opening approximately 31x40cm — use a 30x40cm frame with a mat, or a 40x50cm frame for a wider border.
Mat board can be cut to size by most print shops and professional framers. The mat opening should be cut 3–4mm smaller than the print on each edge to overlap the print and prevent it from falling through.
A3, A2, and A1 Frame Sizes
A3 (29.7x42cm): Requires an A3-specific frame for no-mat display, or approximately a 40x50cm or 40x60cm frame with a mat.
A2 (42x59.4cm): Requires an A2-specific frame for no-mat display, or approximately a 50x70cm or 60x80cm frame with a mat.
A1 (59.4x84.1cm): Requires an A1-specific frame for no-mat display, or approximately a 70x100cm frame with a mat.
Why A-Series Sizes Don't Match Standard Frame Sizes
A-series paper sizes have a specific aspect ratio — 1:√2, approximately 1:1.414 — that was designed for paper folding consistency, not for frame standardisation. Most common frame sizes have slightly different aspect ratios. This is why A4 doesn't fit a 20x30cm frame (which has a 2:3 aspect ratio) without a mat.
The simplest solution for A-series prints is to buy frames specifically labelled for the A-series size. For mixed-size gallery walls where you want consistent frame proportions, ordering prints at standard frame sizes — 20x25cm, 30x40cm — avoids the aspect ratio mismatch entirely.
Browse ONE MAAY's picture frame collection including A-series compatible frames.
