Image DPI Checker
Check an image’s DPI or PPI and calculate its print dimensions, to see whether it has enough pixels for the print you have in mind.
Your file
Why use this tool
- No file size limit
- Nothing is uploaded
- No signup needed
The checker reads the resolution stored in the file, if there is one, and shows the image’s pixel dimensions with the print sizes they give. Type a print size to get the resolution that print would actually have. Everything happens in your browser, and nothing is uploaded.
How to check the DPI of an image
Add your image
Drag it onto the checker, click to choose it, or paste it with Ctrl+V.
Read the DPI and print sizes
See the DPI stored in the file, or a note that there is none, plus the pixel dimensions and the print size at 300 and 150 PPI.
Try your print size
Enter the width or height you want to print, and the checker shows the effective resolution at that size.
DPI vs PPI: what is the difference?
PPI, pixels per inch, describes a digital image: how many of its pixels go into each inch of a print. DPI, dots per inch, strictly describes a printer laying down ink. In everyday use, and in most software, the two are used for the same thing, and the number stored in an image file is usually labelled DPI. It is only a note for printing software. Changing it does not add or remove a single pixel, and many files, such as screenshots and web images, store none at all.
What 300 DPI means for printing
300 DPI (strictly, 300 PPI) is the resolution printers and photo labs commonly ask for when a print will be looked at closely, such as photos, flyers and books. It means 300 of the image’s pixels across every inch of paper. Prints seen from further away, such as posters and banners, are often fine at 150 PPI or less, and screens ignore the number entirely. These are guidelines, not guarantees: a blurry or heavily compressed photo stays blurry at any resolution.
How to calculate print size from pixels
Print size is pixels divided by resolution. An image 3000 pixels wide prints 10 inches (25.4 cm) wide at 300 PPI, or 20 inches at 150 PPI. Turning it around, a print 8 inches wide at 300 PPI needs 2400 pixels across. If an image is too small for the print you want, print it smaller or find a larger original; enlarging it with the image resizer adds pixels but not real detail. To see the rest of an image’s details, use the image size checker.
Check DPI on Windows, Mac or in Photoshop
On Windows, right-click the image, choose Properties and open the Details tab: Horizontal resolution and Vertical resolution are the stored DPI. On a Mac, open the image in Preview and choose Tools, then Show Inspector, to see Image DPI. In Photoshop, Image, then Image Size shows it as Resolution. All of them show only the stored number; the checker above also works out the print size and the effective resolution for you.
Pixels needed for common print sizes
How many pixels an image needs to print each size at 300 DPI, for prints seen up close, and at 150 DPI, for prints seen from a distance. Compare them with your image’s pixel dimensions.
| Print size | Pixels at 300 DPI | Pixels at 150 DPI |
|---|---|---|
| 4 × 6 in | 1200 × 1800 | 600 × 900 |
| 5 × 7 in | 1500 × 2100 | 750 × 1050 |
| 8 × 10 in | 2400 × 3000 | 1200 × 1500 |
| 8.5 × 11 in (US Letter) | 2550 × 3300 | 1275 × 1650 |
| A4 (210 × 297 mm) | 2480 × 3508 | 1240 × 1754 |
| A3 (297 × 420 mm) | 3508 × 4961 | 1754 × 2480 |
| 18 × 24 in poster | 5400 × 7200 | 2700 × 3600 |