Camera Megapixel Calculator
Calculate a camera or image's megapixel count from its pixel width and height, or find the pixel dimensions for a target megapixel count and aspect ratio.
Result
Megapixels
12.00
MP
How to Use the Camera Megapixel Calculator
A camera sensor's resolution in megapixels is simply the total number of pixels it captures, expressed in millions. Enter the pixel width and height of an image (found in your camera's specs or an image file's properties) to calculate its megapixel count, or switch to the reverse mode to work backward from a target megapixel count and aspect ratio to find the pixel dimensions that would produce it.
For the reverse calculation, the calculator solves for height using Height = √(Total Pixels ÷ Aspect Ratio), then multiplies by the aspect ratio to get the matching width.
Example
An image that is 4000 × 3000 pixels has 4000 × 3000 = 12,000,000 pixels, or 12 megapixels — a common resolution for smartphone and entry-level camera sensors. Working backward, if you want a 24 megapixel image at a 3:2 ratio, the calculator suggests roughly 6000 × 4000 pixels.
Common Sensor Resolutions for Reference
| Megapixels | Typical Use |
|---|---|
| 12 MP | iPhone/smartphone main camera (common) |
| 24 MP | Entry-level to mid-range mirrorless/DSLR |
| 48 MP | Flagship smartphone sensors, high-res mirrorless |
| 108 MP | High-megapixel smartphone sensors |
Common Use Cases
- Checking whether a camera or phone's pixel dimensions match its advertised megapixel rating.
- Figuring out the pixel dimensions needed to hit a target megapixel count before shooting or exporting.
- Comparing sensor resolutions across cameras when shopping for new gear.
FAQs
- Does more megapixels always mean a better photo? No — megapixels only measure resolution (detail and print/crop size), not image quality. Sensor size, lens quality, and pixel size affect noise and dynamic range far more than raw megapixel count.
- Why doesn't my camera's exact pixel count match its advertised megapixels? Manufacturers round the true pixel count to the nearest whole megapixel for marketing, and some pixels around the sensor edge are used for calibration rather than the final image, so the effective count is often slightly lower than the total count.
- How do I pick the right aspect ratio for the reverse calculation? Use 3:2 for typical DSLR/mirrorless photos, 4:3 for most smartphone and compact camera photos, 16:9 for widescreen video frames, and 1:1 for square formats like some social media posts.