Calculating your print width is straightforward once you know the Print Size formula and what each input means. This guide explains the method in plain language, walks through a manual calculation, and gives worked examples you can follow — then you can do it instantly with the Print Size Calculator.
What is Print Size?
The Print Size calculation tells you your print width from a few simple inputs. The figure you are solving for here is the print width.
The Print Size formula
The core formula is:
Print width = Image width ÷ Print resolutionHere is what each input means:
- Image width — a value measured in px. Example: 6,000 px.
- Image height — a value measured in px. Example: 4,000 px.
- Print resolution — a value measured in DPI. Example: 300 DPI.
How to calculate it step by step
- Write down the image width (for example, 6,000 px).
- Write down the image height (for example, 4,000 px).
- Write down the print resolution (for example, 300 DPI).
- Apply the formula above to get your print width.
- Double-check the result with the Print Size Calculator.
Worked examples
Example 1
| Input / Output | Value |
|---|---|
| Image width | 6,000 px |
| Image height | 4,000 px |
| Print resolution | 300 DPI |
| Print width | 20.00 |
| Print height | 13.33 |
With image width of 6,000 px, image height of 4,000 px and print resolution of 300 DPI, the print width works out to 20.00.
Example 2
With image width of 12,000 px, image height of 4,000 px and print resolution of 300 DPI, the print width works out to 40.00.
| Result | Value |
|---|---|
| Print width | 40.00 |
| Print height | 13.33 |
Example 3
With image width of 3,000 px, image height of 4,000 px and print resolution of 300 DPI, the print width works out to 10.00.
| Result | Value |
|---|---|
| Print width | 10.00 |
| Print height | 13.33 |
Tips for an accurate result
- Keep your units consistent — mixing, say, months with years or grams with kilograms is the most common source of error.
- Round only at the very end. Rounding inputs early can shift the final answer noticeably.
- Re-run the numbers whenever an input changes, rather than estimating from an old result.
Prefer not to do the maths by hand? — the Print Size Calculator does it instantly, for free, with the formula and a worked example built in.
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