Image guide
How to check image size and resolution
Image size can mean two different things: file size measured in KB or MB, and pixel dimensions measured as width × height. Both matter for uploads, websites, email and printing.
File size in KB or MB
File size depends on the image format, compression quality, dimensions and visual complexity. Two photos with identical dimensions can have different file sizes.
Pixel dimensions and megapixels
Multiply width by height to calculate total pixels. Divide by one million for megapixels. For example, 4000 × 3000 equals 12 megapixels.
Aspect ratio
The aspect ratio describes the shape, such as 1:1, 4:3 or 16:9. Preserving the ratio prevents stretching when resizing.
Print size
At 300 DPI, divide pixel dimensions by 300 to estimate print size in inches. Lower DPI creates a larger print but may reduce sharpness.