Megapixel
Also known as: MP, megapixels, camera resolution
A megapixel is one million pixels, and it describes how many pixels make up a photo. More megapixels capture more detail but produce larger files, so a higher-MP camera fills your storage faster for the same number of shots.
- One megapixel equals one million pixels
- More megapixels mean more detail and larger files
- Format and compression change size for the same MP
What the number means
Megapixels are simply the width of an image in pixels multiplied by its height, divided by one million. A 12 MP photo is roughly 4032 × 3024 pixels; a 48 MP shot has four times as many pixels and captures finer detail.
More megapixels mainly help when you crop, zoom, or print large. On a phone screen the difference is usually invisible, but the file is real: a higher-resolution image stores more data and therefore takes more space.
Why it matters for storage
File size scales with pixel count. Shooting at 48 MP instead of 12 MP can multiply the size of every photo, and modern phones often default to a high-resolution mode that adds up quickly across a full camera roll.
If you do not need maximum detail, choosing a lower-resolution capture mode in your camera settings keeps files smaller. Compression and format also matter — the same megapixel count is far smaller as HEIC than as an uncompressed image.