The pixels to cm formula
A print size depends on two numbers: how many pixels the image has, and how many of them go into each inch of paper, the DPI. Divide the pixels by the DPI and you have inches. Multiply by 2.54 for centimetres.
- Centimetres: pixels ÷ DPI × 2.54
- Millimetres: pixels ÷ DPI × 25.4
- Inches: pixels ÷ DPI
For example, 1200 pixels at 300 DPI is 1200 ÷ 300 = 4 inches, and 4 × 2.54 = 10.16 cm. The 1800-pixel height gives 6 inches, or 15.24 cm. So a 1200 × 1800 px image is a 4 × 6 in print at 300 DPI.
How long 100 and 1000 pixels are at each DPI
| DPI | 100 px | 1000 px | 1000 px in inches |
|---|---|---|---|
| 72 | 3.53 cm | 35.28 cm | 13.89 in |
| 96 | 2.65 cm | 26.46 cm | 10.42 in |
| 150 | 1.69 cm | 16.93 cm | 6.67 in |
| 200 | 1.27 cm | 12.7 cm | 5 in |
| 300 | 0.85 cm | 8.47 cm | 3.33 in |
| 600 | 0.42 cm | 4.23 cm | 1.67 in |
Common image sizes and how big they print
Print sizes at 300 DPI, the usual figure for sharp photo prints, and at 150 DPI for comparison. Width comes first, then height.
| Image | At 300 DPI | At 150 DPI |
|---|---|---|
| 200 × 230 px (IBPS and SBI form photo) | 1.69 × 1.95 cm | 3.39 × 3.89 cm |
| 413 × 531 px | 3.5 × 4.5 cm | 6.99 × 8.99 cm |
| 600 × 600 px | 5.08 × 5.08 cm (2 × 2 in) | 10.16 × 10.16 cm |
| 1080 × 1080 px | 9.14 × 9.14 cm | 18.29 × 18.29 cm |
| 1200 × 1800 px | 10.16 × 15.24 cm (4 × 6 in) | 20.32 × 30.48 cm |
| 1920 × 1080 px | 16.26 × 9.14 cm | 32.51 × 18.29 cm |
| 2480 × 3508 px | 21 × 29.7 cm (A4) | 41.99 × 59.4 cm |
| 3024 × 4032 px (common phone photo) | 25.6 × 34.14 cm | 51.21 × 68.28 cm |
The first row shows why uploads and prints are different jobs. 200 × 230 px is the size the IBPS and SBI photo preset makes for those forms, yet at 300 DPI it would print smaller than 2 × 2 cm. For an upload, follow the pixels and KB the form states. For a print, follow the size you want on paper.
Finding your image's pixels and DPI
Every image has a pixel width and height. The Image Size Checker shows them, along with the exact file size in KB and any DPI stored in the file, without uploading the photo.
Many files carry no DPI at all. Software then has to assume one, usually 72 or 96 DPI, which is why the same photo can show a different size in cm in different apps. The pixels are the same in every case.
For printing, the size you choose matters more than the stored tag. Decide how big you want the print, then check the DPI it gives: divide the pixels by the inches. 300 DPI is the usual target for sharp photo prints. If your print shop gives a figure of its own, use that.
The same pixels at a different DPI
DPI is a setting, not part of the picture. Changing it leaves every pixel as it was and only changes how large the image prints:
| 1200 × 1800 px at | Print size in cm | In inches |
|---|---|---|
| 72 DPI | 42.33 × 63.5 cm | 16.67 × 25 in |
| 96 DPI | 31.75 × 47.63 cm | 12.5 × 18.75 in |
| 150 DPI | 20.32 × 30.48 cm | 8 × 12 in |
| 200 DPI | 15.24 × 22.86 cm | 6 × 9 in |
| 300 DPI | 10.16 × 15.24 cm | 4 × 6 in |
| 600 DPI | 5.08 × 7.62 cm | 2 × 3 in |
Screens ignore DPI. On a phone or a web page the image is drawn by its pixels and fitted to the space available, so the size in cm you work out here applies to paper only.
To store a different DPI in a JPG or PNG without resampling it, use the DPI Converter. It changes the print size the file reports, not its sharpness.
When the print would be too small
- Print at a lower DPI. 1200 × 1800 px covers 20.32 × 30.48 cm at 150 DPI. With half as many pixels per inch, it looks softer up close than the same image at 300 DPI.
- Enlarge the pixels. Resize Image can set a larger print size, and the AI Image Upscaler enlarges an image 2× or 4×. Neither can bring back detail the original never had.
- Start from the original file. A photo saved from a chat app or taken as a screenshot often has fewer pixels than the camera original.
To go the other way, from a print size to the pixels it needs, use the CM to Pixels Converter, or Inches to Pixels for sizes such as 4 × 6 in.