Megapixel Calculator
Use common ratios and resolution presets to convert between pixel dimensions, total megapixels, and aspect ratio. Everything runs locally.
A QUICK WALKTHROUGH
How to use this tool
- Enter width and height to read megapixels and the reduced ratio, or switch to megapixels and ratio to calculate dimensions.
- Choose a common ratio, megapixel target, or 4K/8K preset when useful.
- Review the nearest integer dimensions and total pixel count.
Two-way conversion
Width × height gives total pixels and megapixels. Given megapixels and a width:height ratio, the tool finds the nearest integer dimensions with that ratio.
Common sizes
The table includes common 1:1, 4:3, 3:2, 16:9, and 21:9 sizes plus 12, 24, 32, 45, and 61 MP targets and 4K/8K presets.
Local-only math
No image is selected, uploaded, stored, or inspected. Values are calculated in this browser tab.
GOOD TO KNOW
Common questions
Are the calculated dimensions exact?
They are the nearest integer dimensions for the requested pixel total and ratio; rounding can make the final total differ slightly.
Which megapixel definition is used?
One megapixel is treated as 1,000,000 pixels.
Does the tool process an image?
No. It only performs local arithmetic on the numbers you enter.