Set a width, a height or both, keep the proportions if you want, and export the result at the exact pixel size you need.
Runs in your browser — nothing is uploaded
Most platforms publish fixed dimensions. A store listing expects square product photos, an email client limits the width of a banner, and an app icon needs exactly 512 by 512 pixels. Resizing to those numbers before upload avoids awkward cropping and keeps file sizes under control.
Fill in one side and leave the other empty to keep the aspect ratio automatically. With the ratio locked and both sides filled, the image is scaled to fit inside that box without distortion. Turn the lock off to stretch the picture to exact dimensions, which distorts it when the ratio differs.
Shrinking an image keeps detail well. Enlarging cannot add information that the original does not have, so start from the highest-resolution source you have when you need a larger print.
Leave the Keep aspect ratio box checked and fill only one side, such as a width of 1200. The other side is calculated from the original ratio, so a 4000 × 3000 photo becomes 1200 × 900. Filling both sides with the lock on fits the image inside that rectangle and keeps every proportion.
The image is stretched to exactly the width and height you enter. Use this only when you deliberately need a fixed frame, because faces and text will look squeezed or stretched. For a fixed frame without distortion, use the image cropper instead.
Usually yes, because there are fewer pixels to store. Choosing JPEG or WebP reduces it further. Enlarging an image makes the file bigger without adding real detail, so keep the output at or below the original size unless a platform requires more pixels.
Reducing size keeps detail well, because the browser averages neighbouring pixels with high-quality smoothing. Enlarging cannot recover missing detail, so edges may look soft at larger sizes. The resizer uses the best smoothing setting the browser offers.
Empty fields are allowed while you type. When one side is empty, the tool derives it from the other side. Leave both empty to keep the original size. Only invalid values, such as zero, decimals outside the range or numbers above 8000 pixels, produce an error message.
No. Resizing draws the image onto a canvas inside your browser and produces a download. The file never leaves your device, which matters for unreleased product shots, documents and private family photos.