Reading dimensions
Dimensions are always written as width by height, such as 1,920 by 1,080. The first number counts pixels across, the second counts them down, and their product is the total pixel count.
Nearly every photo app shows these numbers in the file information panel, and the same values appear in most upload forms that restrict image size.
Dimensions versus file size
The two are related but separate. Dimensions count pixels, while file size counts stored bytes. Doubling both dimensions quadruples the pixel data, so size climbs quickly even when nothing else changes.
Compression is the other lever. Two images with identical dimensions can differ enormously in weight depending on format and quality settings, which is why fixing a large file often means adjusting both.
- Width and height are measured in pixels
- Total pixels equal width multiplied by height
- Fewer pixels usually mean a smaller file
- Compression changes size without changing dimensions
Choosing dimensions for the job
Size images for where they will appear. Web images rarely need to be wider than the largest place they will show, and oversized copies only waste bandwidth and risk failing an upload limit.
Filekind resize workflows scale both dimensions together so the shape stays intact, within the shared limits of 16,000 pixels per side and 48 megapixels. Everything runs in the browser without an upload.