DPI Calculator – Print DPI, Screen PPI & Mouse eDPI
Use this free DPI calculator to find the right resolution for any print, the pixel density of any screen, or your mouse’s effective DPI. Instant results, nothing to install.
This calculator does the math from numbers you enter. To test what your mouse sensor actually reports, use the DPI Analyzer.
What Is DPI?
DPI stands for dots per inch. In printing, it is how many dots of ink a printer lays down across one inch of paper. In everyday use it is often swapped with PPI (pixels per inch), which describes how many pixels of a digital image or screen fit into one inch. For mice, DPI describes how sensitive the sensor is: how far the cursor moves for each inch you move the mouse.
Three numbers are always linked: pixel dimensions, physical size, and DPI. Know any two and the third is fixed, which is exactly what the Print / Image tab solves.
DPI Formulas
Example: a 3000 × 2400 px photo printed at 10 × 8 inches gives 3000 ÷ 10 = 300 DPI. To print 8 × 10 inches at 300 DPI you need 2400 × 3000 pixels.
DPI vs PPI vs eDPI
| Term | Meaning | Used for |
|---|---|---|
| DPI | Dots of ink per inch of paper | Printers, scanners, mouse sensors |
| PPI | Pixels per inch of a digital image or screen | Monitors, phones, image files |
| eDPI | Mouse DPI multiplied by in-game sensitivity | Comparing gaming sensitivity |
Recommended DPI by Use
| Use case | Recommended DPI |
|---|---|
| Photos, cards, book pages, small framed prints | 300 |
| Posters and larger wall art | 150 – 200 |
| Billboards and banners (viewed from far away) | 20 – 100 |
| Web and on-screen images | 72 – 96 PPI |
| Scanning documents | 300 – 600 |
| Mouse for FPS gaming (common range) | 400 – 1600 |
These are general guidelines. Viewing distance matters: the farther away a print is seen, the lower the DPI it can get away with.
How to Use This DPI Calculator
Choose a Mode
Pick Print / Image, Screen PPI, or Mouse eDPI, then choose what you want to solve for.
Enter Your Numbers
Type in pixels, print size, screen diagonal, or sensitivity. Quick presets fill common sizes for you.
Read the Result
Results update instantly with a quality rating, megapixels, and aspect ratio. Copy the result with one click.
Tips for Better Print Quality
Aim for 300 DPI at the final print size for anything held in the hand.
Match the aspect ratio of your image to the paper, or crop first, so nothing is cut off unexpectedly.
Do not upscale a small image to hit a DPI number. It adds pixels, not real detail.
For large posters, 150 to 200 DPI is usually fine because they are viewed from farther away.
Print shops recompute their own pixels per inch from your paper size and ignore the DPI tag in the file.
Keep the original full-resolution file. Export smaller copies only for the web.
DPI Calculator – Frequently Asked Questions
Related Tools
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Calculate Your DPI Now
Get the right DPI for prints, screens, or your mouse in seconds.