Megapixel Calculator
Enter the width and height of an image in pixels to get its megapixel count, along with the largest size it can sensibly print.
How to calculate megapixels
Multiply the width by the height and divide by one million: MP = (width × height) ÷ 1,000,000. A 6000 × 4000 sensor is 24,000,000 pixels, or 24 megapixels.
Camera makers round generously, so a sensor sold as 24 MP may measure 24.2 or 23.8. The rounding never matters in practice — a difference of a few per cent in pixel count is invisible in print.
How many megapixels do you need?
At 300 DPI, 8 megapixels covers an A4 page, 12 megapixels covers 8 × 10 inches with room to crop, and 24 megapixels prints comfortably to 20 × 13 inches. Beyond that, viewing distance usually matters more than the pixel count.
Megapixels tell you nothing about lens quality, dynamic range or noise. They only set the ceiling on print size.
Reference table
| Megapixels | Typical dimensions | Max print at 300 DPI |
|---|---|---|
| 2 MP | 1920 × 1080 | 6.4 × 3.6 in |
| 8 MP | 3840 × 2160 | 12.8 × 7.2 in |
| 12 MP | 4000 × 3000 | 13.3 × 10 in |
| 24 MP | 6000 × 4000 | 20 × 13.3 in |
| 45 MP | 8256 × 5504 | 27.5 × 18.3 in |
| 102 MP | 11648 × 8736 | 38.8 × 29.1 in |
Frequently asked questions
How many megapixels is 4K?
8.3 megapixels — 3840 × 2160 is 8,294,400 pixels. It is called 4K for its width in thousands, not its megapixel count, which is why an 8 MP photo and a 4K video frame hold almost the same number of pixels.
How many pixels is 1 megapixel?
One megapixel is one million pixels — for example 1224 × 816, or 1000 × 1000.
How many megapixels is A4 at 150 DPI?
2.2 megapixels — 1240 × 1754 pixels. That is a quarter of the 8.7 megapixels the same page needs at 300 DPI, because halving the density halves both edges.
Are more megapixels always better?
No. Past the resolution your print size needs, extra megapixels only make files larger. Lens quality and sensor performance matter far more to the finished image.