Print Resolution Calculator
Check whether your photo has enough resolution for a sharp print at the size you want it framed — before you spend money on a print that turns out soft.
Resolution
Effective PPI uses the more pixel-starved of the two dimensions — that’s the one that determines whether the print looks sharp up close.
Resolution is relative to print size, not a fixed number
A photo with plenty of pixels for a small print can fall well short at poster size — resolution (PPI) is always relative to how large you're printing, not a property of the file on its own. The same 12-megapixel photo might be comfortably sharp at 8×10 and visibly soft blown up to 24×36.
Checking PPI before ordering a print, especially an enlargement, avoids paying for a piece that looks soft once it's framed and on the wall — and the minimum-pixels figure works the other way, telling you upfront what a future large print will need.
Frequently Asked Questions
How is PPI calculated?
PPI (pixels per inch) is your photo's pixel dimension divided by the physical print size in inches on that same axis — a 2400-pixel-wide image printed at 8 inches wide gives 2400 ÷ 8 = 300 PPI. The calculator does this for both width and height, since a photo isn't always cropped to the exact ratio of the print, and reports the lower of the two as the effective PPI — that's the dimension that will actually look softer if resolution is short.
What PPI do I actually need for a sharp print?
300 PPI is the common benchmark for prints viewed up close, like a photo held in hand or a small framed piece at normal reading distance. Larger prints meant to be viewed from farther away — posters, large canvas prints — can look perfectly sharp at 150–200 PPI, because the viewing distance itself reduces how much detail the eye can resolve.
My print size is in centimetres — does the calculator handle that?
Yes. PPI is inherently an inches measurement, so when you select centimetres the calculator converts your print dimensions to inches (dividing by 2.54) before computing PPI. You still get the print size in the unit you're used to; only the internal math changes.
What does the minimum pixel dimensions figure tell me?
It runs the same formula in reverse: given the print size you want and a target PPI, it multiplies them to tell you the smallest pixel dimensions the source image needs. It's a quick sanity check before ordering an enlargement, or before re-shooting a photo you know needs to end up large.
What happens if my photo falls short of the target PPI?
The print will look progressively softer or more pixelated the further short it falls — mildly at 200 PPI for a piece viewed from a normal distance, noticeably at 100 PPI or below for anything viewed up close. Upscaling software can improve the look somewhat but can't invent detail that was never captured, so it's not a full substitute for enough native resolution.
Educational estimate — actual perceived sharpness also depends on viewing distance, the print lab's process, and the original photo's focus and noise, not resolution alone.