Photography Math: Exposure, Depth of Field and Crop Factor
The numbers that sharpen your photography — the exposure triangle, exposure value, depth of field and hyperfocal distance, crop factor, flash guide numbers and print size.
Print Size Calculator
Verified formula Updated Jun 2026 Private — runs on your device
Verified formula
Private
Print width
20.00
- Print height
- 13.33
For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.
How to use the Print Size Calculator
The Print Size Calculator works out your print width, along with 1 related figure in an instant. Enter image width, image height and print resolution and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.
- Enter the image width.
- Enter the image height.
- Enter the print resolution.
- Read off your print width, together with print height — the calculator updates automatically, with no button to press.
Formula
The Print Size Calculator uses the formula:
Print width = Image width ÷ Print resolution
Worked example
For example, with image width of 6,000 px, image height of 4,000 px and print resolution of 300 DPI, the print width is 20.00.
| Image width | 6,000 px |
|---|---|
| Image height | 4,000 px |
| Print resolution | 300 DPI |
| Print width | 20.00 |
|---|---|
| Print height | 13.33 |
Results are estimates for educational use, not professional advice.
Frequently asked questions
Divide each pixel dimension by the DPI. A 6000 × 4000 image at 300 DPI prints at 20 × 13.3 inches.
300 DPI is standard for sharp photo prints. Large prints viewed from a distance can use 150–200 DPI.
A lower DPI spreads the same pixels over a larger print, so you can print bigger but with less fine detail.
Yes, but quality drops as DPI falls. Upscaling software can help, though it cannot add true detail that was never captured.
The Print Size Calculator uses the formula: Print width = Image width ÷ Print resolution. For example, with image width of 6,000 px, image height of 4,000 px and print resolution of 300 DPI, the print width is 20.00.
Enter the image width. Enter the image height. Enter the print resolution. Read off your print width, together with print height — the calculator updates automatically, with no button to press.
Related guides
Print Size Table: Print width by Image width
Reference table of print width for Print Size across a range of image width values — exact, engine-computed figures you can read off at a glance.
How to Calculate Print Size: Formula, Steps & Examples
Learn how to calculate Print Size — the formula explained step by step, with worked examples and a free calculator to check your answer.
Crop Factor Table: Full-frame equivalent focal length by Lens focal length
Reference table of full-frame equivalent focal length for Crop Factor across a range of lens focal length values — exact, engine-computed figures you can read off at a glance.