One of the most misunderstood concepts in digital images. Here is the simple explanation.
A pixel is the smallest unit of a digital image. An image described as 1920 x 1080 contains 1,920 pixels horizontally and 1,080 pixels vertically -- approximately 2 million pixels total. The pixel count determines how much visual information the image contains. More pixels means more detail.
DPI (dots per inch) describes how densely pixels are packed when an image is printed. A 300 DPI image has 300 pixels per inch of printed paper. DPI is a print instruction, not a property of the digital file itself. Changing the DPI of an image does not add or remove pixels -- it only changes how large the image prints.
Screens display images pixel-for-pixel. A 1920x1080 image fills a 1920x1080 screen regardless of whether the file says 72 DPI, 300 DPI, or 1 DPI. Web browsers ignore the DPI metadata entirely. What matters for web images is pixel count and file size, not DPI.
| Context | Required DPI | Why |
|---|---|---|
| Web / screen display | Irrelevant | Browsers use pixel count only |
| Office printing | 150-200 DPI | Acceptable quality for documents |
| Photo printing | 300 DPI | Standard for sharp photographic prints |
| Large format / banners | 72-150 DPI | Viewed from a distance, lower DPI acceptable |
| Professional press | 300+ DPI | Required by print shops |
Divide your pixel dimensions by the target DPI to find the print size in inches.
Example: A 3000 x 2000 pixel image at 300 DPI prints at 10 x 6.67 inches. The same image at 150 DPI prints at 20 x 13.33 inches, but with lower sharpness.
For web: focus on pixel dimensions and file size. Use our Image Cropper to set exact pixel dimensions, and the Image Compressor to minimize file size. Check our Social Media Image Sizes Guide for platform-specific pixel requirements.
No. Changing DPI only changes the print instruction metadata. The actual pixel data remains identical. A 3000x2000 image is the same quality whether it is tagged as 72 DPI or 300 DPI.
This is a legacy convention from early Macintosh displays. It has no practical impact today. What they actually mean is to provide images at the correct pixel dimensions for web display.
Multiply the desired print size in inches by 300. For an 8x10 inch print at 300 DPI, you need 2400 x 3000 pixels. For large posters viewed from a distance, 150 DPI is often sufficient.