Counting megapixels
Multiply pixel width by pixel height and divide by a million. A 6,000 by 4,000 image holds 24 million pixels, which is 24 megapixels, and the same math works in reverse to find dimensions from a count.
Sensors often report a slightly higher number than the final photo, because some pixels are cropped or used for stabilization. The image you actually keep is what matters for file size and detail.
How many megapixels you need
Screen viewing needs far fewer pixels than large prints. A phone display shows a fraction of what a modern sensor captures, so extra pixels mostly buy headroom for cropping.
More pixels also mean heavier files. Storage, upload limits, and editing speed all respond to pixel count, which is why oversized images are often reduced before sharing.
- Social posts and web galleries: modest counts are enough
- Heavy cropping: extra pixels preserve detail after the cut
- Large prints: density matters more than raw count
- Uploads: fewer pixels help clear size limits
Megapixels and Filekind limits
Filekind caps input at 48 megapixels and 16,000 pixels per side, which comfortably covers most phone and consumer camera output while keeping in-browser processing fast. Files inside those ceilings can still be resized down when the destination only needs a fraction of the available pixels.
When a file exceeds what a form allows, reducing the pixel count is usually the most effective fix, followed by stronger compression for what remains.