What Megapixels Really Mean, and When More Is Not Better

Phone makers love to advertise megapixels. But what do they tell you, and what don't they?

What a megapixel is

One megapixel (MP) is one million pixels. A 12 MP photo has around 12 million pixels, for example 4000 × 3000.

What more megapixels give you

• Larger dimensions, so you can print bigger or crop harder.
• More room to crop a distant subject and still keep detail.
• Bigger files.

What they don't guarantee

Photo quality depends on much more:

Factor	Effect
Sensor size	bigger sensors collect more light, giving cleaner low-light photos
Lens quality	affects sharpness, colour and distortion
Image processing	how the phone handles noise, colour and detail
Lighting	good light beats extra pixels
Steadiness	camera shake blurs any resolution

A 12 MP photo in good light often looks better than a 48 MP photo taken in the dark.

Many phones combine pixels

Some high-megapixel phones combine groups of neighbouring pixels into one to make cleaner 12 MP images by default. The full-resolution mode is optional, and files are much larger.

How many do you need?

Use	Megapixels needed
Sharing online	1 to 2
Full-screen on a laptop	about 2
A 4 × 6 inch print	about 2
An A4 print	about 8
Cropping heavily	more helps

Most people rarely need more than 12 MP.

The storage cost

Higher resolution means larger files. A phone with a 48 MP mode can fill storage quickly. If you don't need the extra detail, use the standard mode.

Reducing size later

If you've shot at high resolution and want to share, resize to a smaller size. You lose pixels but keep the look, and files become quick to upload.

With a resizing tool

Keep the original for editing and printing, and make a smaller copy for sharing. Cropping and resizing with a compact app keeps the workflow fast.

Try Image Compress & Resize Tool →