How to resize an image
Move the slider to scale the image relative to its current dimensions — 50% halves both sides, 200% doubles them. The image is redrawn at the new dimensions using the browser's own scaling, then saved in the format you choose. Batch mode handles several files with the same settings.
Keeping images sharp
- Scaling down almost always looks good. Scaling far up does not add detail — it only stretches the pixels that exist.
- Keep the aspect ratio unless you deliberately want a stretched image. When a fixed width and height are required, the crop-to-fill option trims the overflow instead of distorting the picture.
- Resize from the largest original you have rather than from a copy that was already reduced.
- Save photographs as JPG or WebP, and flat graphics or anything with transparency as PNG or WebP.
Dimensions, resolution and file size
Screen images are measured in pixels; DPI only matters for print. Halving both the width and the height removes about three quarters of the pixels, which is usually the fastest way to make a heavy image light. If the file is still too big afterwards, run it through a compressor as a second step.