Image Resizer

Pixels, proportions, and file size

Resizing changes the number of pixels in an image. Reducing a 4000 × 3000 photograph to 1200 × 900 keeps its 4:3 proportions but retains only 9% of the original pixel count. The smaller copy is often easier to share.

Changing a DPI label alone does not reduce pixel dimensions. This tool resamples the actual pixels. It does not crop: unlocking the aspect ratio and choosing different proportions stretches the image.

Resize or compress?

Resize when an image contains more pixels than its destination needs. Compress when the dimensions are already appropriate but the byte size is too large. For an oversized photograph, resize first, then adjust compression.

Enlarging a small image adds interpolated pixels, not captured detail. Keep the source file for printing and use a separate smaller copy online.

Useful starting dimensions

These are general working sizes, not current platform upload requirements. Check the destination before publishing.

Example: a photograph for a smaller display

A 4000 × 3000 image becomes 1200 × 900 when the aspect ratio is locked and the width is set to 1200. Unlocking the ratio and choosing 1200 × 1200 stretches the picture; it does not make a square crop.

JPG output puts transparent pixels on white. PNG and WebP can preserve transparency. Reset releases the current preview and result so you can start with another original.