STILL TOOLS

Picture Frame Size Calculator & Mat Matcher

Enter the dimensions of a painting, photograph, print or reproduction to find a suitable ready-made frame in inches or centimetres. Compare exact fits, ISO A-series formats and larger frames with a mat across a combined global catalogue. Optional regional filters are available under More options.

What did you measure?

WidthHeight

Mat

A mat is the card border around the artwork.

More options

Where you will buy the ready-made frameArtwork hidden under the matShow other units

Your frame: 15.75 × 19.69 in

Your frame

15.75 × 19.69 in

400 × 500 mm · 40 × 50 cm

Ready-made frame · 40 × 50 cm

The ready-made frame changes the border a little

A frame sold in this size.

Narrow, Classic and Wide look for a ready-made frame. Ready-made sizes are fixed, so the border may change. The diagram shows what you will get. Choose Exact width to keep the border you enter.

Mat opening: 11.75 × 15.75 in
What you get at the sides: 2 in
What you get at the top and bottom: 1.97 in
What you chose: 2 in

Frame size means the inner opening, not the outside of the moulding.

The mat opening is slightly smaller than the artwork so it holds it in place.

See it on a wallPlanning a mat in detail? Open the Professional Picture Framing Calculator →

This calculator is provided for information only. Results are estimates based on the measurements you enter. Always check dimensions with your framer or retailer before ordering. STILL is not responsible for purchases made on the basis of these results, to the extent permitted by law. See our Terms of Use for details.

How to measure a picture frame

If you are choosing a new frame, measure the artwork itself. If you already have a frame, measure the glazing or the opening behind the front edge of the moulding. This is the inner frame size, not the outer dimensions of the frame.

Artwork

→ Mat opening

→ Glazing or inner frame size

→ Outer frame size

A mat opening is normally made slightly smaller than the artwork so that its edges remain securely held in place.

Common picture frame sizes

Ready-made frames are produced in both inches and centimetres. Some dimensions appear in several markets, while others are more common in metric, inch-based or ISO paper formats. This calculator combines them in one catalogue and compares the actual dimensions rather than assigning a frame to a particular country.

Common inch frame sizes

4 × 6, 5 × 7, 6 × 8, 8 × 10, 8.5 × 11, 9 × 12, 10 × 12, 11 × 14, 12 × 16, 14 × 18, 16 × 20, 18 × 24, 20 × 24, 20 × 30 and 24 × 36 inches.

Common metric frame sizes

10 × 15, 13 × 18, 15 × 20, 18 × 24, 20 × 25, 20 × 30, 21 × 30, 24 × 30, 30 × 40, 30 × 45, 40 × 50, 40 × 60, 50 × 70, 60 × 80 and 70 × 100 cm.

Square and panoramic frame sizes

Common square formats include 10 × 10, 12 × 12 and 20 × 20 inches, as well as 20 × 20, 30 × 30, 40 × 40, 50 × 50 and 60 × 60 cm. Panoramic and larger metric formats include 40 × 90, 50 × 100, 60 × 120, 70 × 140, 80 × 120, 90 × 120 and 100 × 150 cm.

ISO A-series frame sizes

A6: 105 × 148 mm
A5: 148 × 210 mm
A4: 210 × 297 mm
A3: 297 × 420 mm
A2: 420 × 594 mm
A1: 594 × 841 mm
A0: 841 × 1189 mm

Common frame size conversions

A4 = 21 × 29.7 cm = 8.27 × 11.69 inches
A3 = 29.7 × 42 cm = 11.69 × 16.54 inches
30 × 40 cm = 11.81 × 15.75 inches
50 × 70 cm = 19.69 × 27.56 inches
8 × 10 inches = 20.32 × 25.4 cm
11 × 14 inches = 27.94 × 35.56 cm
16 × 20 inches = 40.64 × 50.8 cm

Converted measurements can be close to a ready-made size without being identical. The calculator checks both dimensions and proportions before suggesting a frame.

Frequently asked questions

How do I choose the correct frame size?

Enter the exact width and height of the artwork. The calculator will check whether a ready-made frame provides an exact fit and whether a larger standard frame can be used with a mat.

Does an 8 × 10 frame fit an 8 × 10 print?

Usually, yes. An 8 × 10 frame normally refers to its inner or glazing size. Check the manufacturer’s specifications because the visible opening at the front may be slightly smaller.

What frame fits an A4 print?

An A4 print measures 210 × 297 mm, or approximately 8.27 × 11.69 inches. An A4 frame provides the closest direct fit. A larger ready-made frame can also be used with a custom mat.

Is 30 × 40 cm the same as 12 × 16 inches?

Not exactly. A 30 × 40 cm print measures approximately 11.81 × 15.75 inches. The formats are close, but their dimensions are not identical.

Does frame size include the border?

Frame size usually describes the inner frame or glazing size, not the outer edge of the moulding. The external dimensions depend on the width and profile of the frame.

How much smaller should a mat opening be?

A mat opening is normally made a few millimetres smaller on each edge so that it overlaps and holds the artwork. This calculator uses an overlap of 3 mm per edge.

What if the aspect ratios do not match?

A different aspect ratio can create uneven mat borders or require part of the image to be cropped. A custom mat or custom-made frame will usually preserve the complete image.