16x20 photo size in cm, mm and pixels
A 16x20 inch photo is 40.64 × 50.8 cm, and 4800 × 6000 pixels at 300 dpi.
16 × 20 in dimensions
| Unit | Short side | Long side |
|---|---|---|
| Inches | 16 in | 20 in |
| Millimetres | 406.4 mm | 508 mm |
| Centimetres | 40.64 cm | 50.8 cm |
| Points (1/72 in) | 1152 | 1440 |
16x20 is double 8x10 in each direction and has the same 5:4 shape, so it needs four times the pixels for the same sharpness.
Pixels and megapixels for a 16 × 20 in print
| Resolution | Pixels needed | Megapixels | Quality |
|---|---|---|---|
| 300 dpi | 4,800 × 6,000 px | 28.8 MP | Best quality; the usual lab target |
| 200 dpi | 3,200 × 4,000 px | 12.8 MP | Good; fine for most prints viewed at arm's length |
| 150 dpi | 2,400 × 3,000 px | 7.2 MP | Acceptable for large prints viewed from a distance |
| 100 dpi | 1,600 × 2,000 px | 3.2 MP | Poster viewed from several metres |
Cropping: which cameras fit a 16 × 20 in print?
A print of this shape has a long side 1.25 times the short side. A camera image with a different shape has to be cropped to fill it, and the crop throws away part of the picture.
| Camera shape | Crop to fill this print | Source needed for 300 dpi | Source needed for 200 dpi |
|---|---|---|---|
| 3:2 (DSLR, mirrorless) | 16.7% of the image is cropped | 34.6 MP | 15.4 MP |
| 4:3 (phones, compacts) | 6.2% of the image is cropped | 30.7 MP | 13.7 MP |
| 16:9 (video frame) | 29.7% of the image is cropped | 41 MP | 18.2 MP |
| 5:4 (large format) | none (exact fit) | 28.8 MP | 12.8 MP |
| 1:1 (square) | 20% of the image is cropped | 36 MP | 16 MP |
Crop is the share of the image length removed along its longer side (or shorter side when the print is more elongated than the image). “Source needed” is the smallest image of that shape that still covers the print at that dpi after cropping.
What your camera gives you at this size
| Camera | Effective resolution when cropped to fill | Rating |
|---|---|---|
| 12 MP phone (4032 × 3024) | 189 dpi | fair |
| 24 MP camera (6000 × 4000) | 250 dpi | good |
| 48 MP phone (8064 × 6048) | 378 dpi | excellent |
Rule of thumb: 300 dpi is the usual target for lab prints and 150 dpi is the floor for a print viewed from a distance. Typical sensor sizes shown; check your own image dimensions.
Frames and mats for a 16 × 20 in print
| Common frame | With a mat | Result |
|---|---|---|
| 20 × 24 in frame | mat window about 15.5 × 19.5 in | 2.25 in of mat visible at each side, 2.25 in top and bottom |
| 24 × 30 in frame | mat window about 15.5 × 19.5 in | 4.25 in of mat visible at each side, 5.25 in top and bottom |
| 22 × 28 in frame | mat window about 15.5 × 19.5 in | 3.25 in of mat visible at each side, 4.25 in top and bottom |
Retail pairings are conventions, not a standard. The mat window is smaller than the print by about 1/4 inch at each edge so the print is held behind the mat; ask your framer, and see all sizes on the picture frame sizes page.
How many pixels is enough at 16x20?
At 300 dpi a 16x20 print needs 28.8 megapixels, more than most cameras produce. Wall prints are viewed from further back than a 4x6 held in the hand, so 150 dpi (7.2 megapixels) is a normal floor and 200 dpi (12.8 megapixels) looks good. The camera table above shows what common cameras give: a 24-megapixel 3:2 camera reaches about 250 dpi when cropped to fill 16x20, a 12-megapixel phone about 190 dpi.
Metric near-equivalents
40x50 cm (400 × 500 mm) is the common metric size: 6.4 mm narrower and 8 mm shorter than 16x20 inches, so it fits in a 16x20 frame with a small gap but a 16x20 print will not fit a 40x50 frame.
Frequently asked questions
What size is 16 x 20 in cm?
40.64 x 50.8 cm (406.4 x 508 mm).
What is 16 x 20 in pixels?
At 300 dpi it is 4,800 x 6,000 pixels; at 200 dpi 3,200 x 4,000; at 150 dpi 2,400 x 3,000.
How many megapixels for a 16 x 20 print?
About 28.8 megapixels for 300 dpi and 12.8 for 200 dpi, before allowing for cropping.
Is 16x20 the same as 40x50 cm?
Almost: 40.64 x 50.8 cm against 40 x 50 cm. A 16x20 print is slightly bigger.
Is a 12 megapixel photo enough for 16x20?
It gives about 190 dpi when cropped to fill 16x20, which is acceptable for a wall print.