megapixels

Megapixels, abbreviated MP, are a unit of image resolution equal to one million pixels. In digital cameras, megapixels describe the total number of pixels in a still image captured by the sensor, or the nominal resolution the sensor can produce. A sensor resolution of 4000 by 3000 pixels, for example, yields 12 MP (4,000 × 3,000 = 12,000,000).

Higher megapixels mean more potential detail for large prints or for cropping, but they do not by themselves guarantee better image quality. Quality depends on multiple factors, including the sensor size, pixel pitch, lens quality, dynamic range, noise performance, and image processing. Smaller sensors with many megapixels can have smaller pixels that collect fewer photons, which can reduce signal-to-noise ratio in low light and limit dynamic range.

Marketing often highlights high MP counts, especially in smartphones, but practical benefits depend on the overall system design. For many users, 12–24 MP strikes a balance between detail and good performance under typical conditions; 30 MP and above may be advantageous for very large prints or substantial cropping, though real-world advantages may be modest in ordinary viewing.

Video resolution is a separate consideration from still-image megapixels, though some cameras enable extracting high-resolution stills from video or recording high-resolution frames. Upsampling a low-MP image to a larger size can display more pixels but does not create new detail; image quality is constrained by the original data.

In summary, megapixels describe potential image size and detail, but true image quality arises from sensor size, optics, processing, and shooting conditions.