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DPI Calculator

Find the effective DPI for a given image and print size.

Updated July 2, 2026

Details

Width (pixels)

Height (pixels)

Print width (inches)

Print height (inches)

Results

Effective DPI -

Width DPI -

Height DPI -

Print quality -

Print size = pixels ÷ DPI.

How Is DPI Calculated From Your Pixels And Print Size

Divide pixel width by the print width in inches, then divide pixel height by the print height in inches. Whichever of those two numbers comes back lower is the one this tool reports, because a mismatched aspect ratio always gets limited by its tightest dimension.

Take the numbers already loaded above: a 6000×4000px file going to a 20 × 13.33 in print. Width comes out to 6000 ÷ 20 = 300. Height comes to 4000 ÷ 13.33 = 300.08. Both round to 300, so the calculator settles on 300 DPI and calls it Excellent, the same bar this page uses for any close-up photo print.

Keep the same file but ask for a 30 × 20 in print instead. Width DPI becomes 6000 ÷ 30 = 200. Height DPI is 4000 ÷ 20 = 200. Nothing about the photo changed, only how much of it you are stretching across a bigger sheet, and the rating slides from Excellent to Good.

Push the same 24-megapixel file to a 40 × 26 in print and width DPI drops to 150, with height landing a touch higher at 154. The lower number wins, so the tool reports 150 DPI, Acceptable, the last stop before quality gets shaky. Go further still, to 70 × 46 in, and the same pixels are now spread thin enough to read as 86 DPI, Low / web, the range this tool flags as unsuitable for a printed piece meant to be examined up close.

What The Quality Rating On This Page Actually Checks

The word next to your result is not a subjective call. It comes straight from the thresholds written into the script on this page, the same ones used in the examples above.

Effective DPI	Rating shown here	Typical fit
300 or higher	Excellent	Photo prints and portraits viewed at arm's length
200 to 299	Good	Wall art viewed a step or two back
150 to 199	Acceptable	Posters and large prints viewed across a room
72 to 149	Low / web	Screen display; risky for a printed piece
Under 72	Too low	Pixelation will show even at a distance

Nothing in that table is sourced from outside this page; it is the same math the two input fields above feed into.

Things To Know Before You Trust A DPI Number

A file's metadata DPI, often 72 or 96, is a screen-display leftover. It has no bearing on how many pixels the file holds, which is the only figure this calculator reads.
When width DPI and height DPI come back more than a point or two apart, the image and the print you asked for do not share the same aspect ratio, and part of the frame will get cropped.
Software can add pixels between the ones you already have. That can raise the number this calculator sees, but it does not add detail the camera never captured.
Distance changes what counts as sharp. A poster read from six feet away can look fine at a DPI that would look soft in a print held in your hands.

Good to know

FAQs

What is DPI?

Dots per inch - how many pixels are packed into each printed inch. Higher means sharper.

What DPI is good for printing?

300 DPI is the standard for sharp photo prints.

Why are width and height DPI different?

If your image and print aspect ratios differ, each dimension yields a different DPI.

Is 150 DPI good enough?

For large prints viewed from a distance, often yes; for handheld photos, aim higher.

How do I increase DPI?

Print smaller, or start from a higher-resolution image.

Related Calculators

Already know the print size you want and need the pixels to match it? Try the pixels-needed calculator. Working from pixels toward a size instead, open the print size tool, or scan the full size-to-pixel table for eight common frames at once.