How to Check an Image’s Resolution on Windows, Mac, iPhone and Android

Step-by-step for every device, which number to look at, and which one to ignore.

By Chris Bezuidenhout · 8 November 2026 · 5 min read

Before you order a print, you need one piece of information: the image’s size in pixels. Here is how to find it on any device, and how to turn it into the largest size you can print.

Look for the pixel dimensions, for example “4032 × 3024”. That is the number that decides print quality. A “DPI” or “resolution” number such as 72 or 96 can be ignored; it doesn’t affect how the image prints. Why the DPI number doesn’t matter.

On Windows

Right-click the image in File Explorer and choose Properties.
Open the Details tab.
Under Image, read Dimensions, for example 6000 × 4000.

Hovering over an image in File Explorer also shows its dimensions in a small pop-up.

On a Mac

Select the image in Finder and press Cmd + I (or right-click and choose Get Info).
Expand More Info and read Dimensions.

In Preview, open the image and choose Tools → Show Inspector to see the pixel size.

On an iPhone or iPad

Open the photo in the Photos app.
Swipe up on the photo, or tap the ⓘ button.
The info panel shows the megapixels and the pixel size, for example “12 MP · 4032 × 3024”.

iPhones save photos as HEIC by default, which many print services don’t accept. See which file formats to use for printing.

On Android

Open the photo in Google Photos (or your phone’s Gallery app).
Swipe up, or tap the ⋮ menu and choose Details or Info.
Read the resolution, for example “12 MP 4000 × 3000”.

In editing apps

Photoshop: Image → Image Size (Alt + Ctrl + I on Windows, Option + Cmd + I on Mac). Make sure the units are set to pixels.
GIMP: Image → Scale Image shows the current width and height in pixels.
Lightroom: the Metadata panel shows the dimensions, and the cropped size after any crop.

In your browser

Upload the image to the PrintCheck checker. It shows the pixel size, whether the image is big enough for the print size you choose, and the largest size it can print sharp. The image is deleted straight after the check.

From pixels to print size

Divide each side by 300 to get the largest sharp print in inches:

largest print (inches) = pixels ÷ 300

A 4032 × 3024 photo prints sharp up to about 13.4 × 10 inches (34 × 26 cm). For wall art viewed from further away, divide by 200 or 150 instead. The megapixels to print size chart has the numbers for common cameras and phones.

Check the right copy

The photo on your phone may be full size, but the copy you upload might not be. Messaging apps, email and social media often shrink images when you share them. Check the exact file you are about to send to the printer, and if it is smaller than expected, go back to the original.

Check your image before you print

Upload a file, pick a print size and PrintCheck tells you in seconds if it will print sharp, needs upscaling, or is too small. Free, no sign-up, and your image is deleted straight after the check.

Check an image free