Try a resize with predictable dimensions: Add the 1200 × 800 practice PNG to Image Resizer. Choose Pixels, set Width to 600 and leave Height on Auto: export should be 600 × 400. Compare with a 600 × 600 box using Fit (600 × 400), Fill (600 × 600 with edges cropped) and Pad (600 × 600 with margins). Keep Allow enlargement off.
Practice file and tool: Download the synthetic practice file · Open the tool
Downscaling is safe; upscaling is guesswork
Making an image smaller combines several source pixels into each new pixel. Done with a good filter, the result looks sharp — often sharper than the original at the same size, because noise averages out. Making an image larger has no new information to draw on; the software has to invent pixels, and the result is soft. The visible change depends on the source, enlargement and display size; inspect text and edges rather than relying on a universal safe percentage.
That is why the resizer does not enlarge unless you ask it to. If a preset or a typed size is larger than your source, the result keeps the proportions at the largest size available and the file details tell you so. Tick Allow enlargement only when a destination insists on a minimum size and a soft image is acceptable.
Keep the aspect ratio
Distortion — squashed faces, oval circles — comes from changing width and height by different factors. In the resizer, fill in only the width or only the height and leave the other side on Auto: each image in the batch keeps its own proportions, so nothing can be stretched. Set both sides only when you deliberately want an exact shape, and then choose how the mismatch is handled.
- Fit: the whole image is scaled to sit inside your width and height. Nothing is cut; the output may be smaller on one side than you typed.
- Fill: the image is scaled to cover the exact size and the overflow is cropped from the edges, centred.
- Pad: the whole image is placed inside the exact size and the remaining area is filled with a background colour — or left transparent in PNG and WebP.
- Stretch: the image is forced to the exact size and its proportions change. Use only for abstract patterns or when someone explicitly wants distortion.
Crop, then resize
The best-looking exact-size images are cropped to the right shape first, then scaled. Cropping chooses what stays in the frame; scaling only changes how big it is. The resizer’s Fill option crops from the centre automatically; when the subject is off-centre, frame it in the cropper first, then send the result to the resizer. The cropper also has its own Resize panel for a one-off edit.
Percentages, long side and DPI
Percentage resizing keeps the ratio by definition and is the quickest way to halve or quarter a batch. If a form asks for a maximum width or height rather than a fixed size, use the resizer’s Longest side mode: landscape images get that width, portrait images that height, and nothing is enlarged.
DPI (dots per inch) is only meaningful for print. A screen shows pixels, not inches, so a 1,200 × 800 image looks the same at 72 or 300 DPI. For print, divide the desired inches into pixels at 300 DPI: a 4 × 6 inch print wants about 1,200 × 1,800 pixels.
Keeping it sharp after export
- Export a resized photo as JPG at quality 85–90 or as WebP; resizing then compressing hard is where visible blur usually comes from.
- Use PNG to avoid adding lossy compression to scaled text; resizing itself still changes the pixels.
- Resize once, from the original. Resizing a resized image compounds the softness.
- Look at the result at 100% before downloading; a fit-to-screen preview hides softness.