Online Tool Store
Print Resolution Checker
Check whether an image's pixel dimensions support a given print size at 300, 240, or 150 DPI, and what the largest good print would be.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Image
Print Resolution Checker
Frontend preview — no upload or external service.
Resolution check
4000 x 3000 px at A3 gives 244 DPI — fine for a photo print viewed at arm's length, marginally short of a 300 DPI fine-art standard.
How the Print Resolution Checker works
- Enter the image's pixel dimensions, or add the file to read them.
- Choose the print size you want.
- Compare the resulting DPI against the target for the viewing distance, not against a universal 300.
The method
Print resolution is pixels divided by physical size, so the DPI you achieve falls as the print grows.
DPI = pixel width / print width in inches
4000 px across a 16.5-inch A3 long edge gives 242 DPI. The same file at A1 gives only 120 DPI — fine for a wall poster, poor for a held print.
FAQ
Is 300 DPI always required?
No. It is a standard for material held at reading distance. A billboard is printed at a fraction of that and looks perfect from the street, because required resolution falls with viewing distance.
Can upscaling fix a low-resolution file?
It can improve appearance, but it cannot recover detail that was never captured. Printing slightly smaller is almost always the better answer.
Does DPI matter for screens?
No. Screens use pixel dimensions directly; the DPI value stored in a file affects print size only, and changing it does not alter image quality at all.
How we compare
| Feature | Online Tool Store | A desktop editor | An upload-based service |
|---|---|---|---|
| Largest good print size | ✓ | Manual | Yes |
| Viewing-distance guidance | ✓ | ✗ | ✗ |
| Image stays on your device | ✓ | ✓ | ✗ |
| No account | ✓ | ✓ | ✗ |
Print Resolution Checker judges against viewing distance rather than a blanket 300 DPI, which is what decides whether a large print actually looks sharp.