Resize Image
Resize JPG, PNG and WebP images by pixel width and height. Keep the aspect ratio and download a new image processed in your browser.
Free · No account required · Browser-basedDrop your image here
One small step to your next great image.
JPEG, PNG, WebP · Up to 25 MiB · 24 megapixels · 10,000 px per sideLimits help protect your browser’s memory.
Local processing. Images selected for this tool are processed in your browser and are not uploaded to 4ool servers. Learn more
How it works
Select an image and check its current dimensions.
Enter a width or height in pixels. Keep aspect ratio on to preserve its shape.
Create the resized copy, inspect the preview and download it.
Pixel dimensions and file size are different
Width and height tell you how many pixels make up an image. File size tells you how much storage its encoded data occupies. A 1200-pixel-wide photograph can have very different file sizes depending on its format, detail and quality.
Choose dimensions for the place the image will appear. Reducing an unnecessarily large image can make it easier to share and quicker to display, while compression controls can further change the encoded file size.
Keep the original proportions
Keep aspect ratio is enabled by default. Changing one dimension calculates the other from the original proportions, with rounding to whole pixels. This avoids making faces look too wide or circles look oval.
Turning the option off lets you set width and height independently, which stretches the image if the proportions change. If you need a particular shape without distortion, crop to that ratio first and then resize.
What resizing can and cannot do
The browser canvas resamples the image with smoothing enabled. Reducing dimensions removes pixel information, so very fine text or lines may become harder to read. Inspect the output at the size where it will be used.
This MVP is intended for reducing or retaining image dimensions. It does not provide image upscaling or reconstruct missing detail. Keep the original if you may need a larger version later.
Format, quality and transparency
The resized copy uses the source format. PNG and WebP can retain transparent pixels; JPG has no transparency. JPG and WebP expose a quality setting because resizing also requires a fresh encode.
The downloaded image is a new file, and source metadata is not preserved as an exact copy. Processing happens locally, with limits on file size and dimensions to reduce memory pressure on browsers and mobile devices.
Frequently asked questions
Why does the height change when I enter a width?
Keep aspect ratio is on by default. It calculates the matching height so that the image keeps its original proportions.
Will resizing make my image smaller in megabytes?
Reducing dimensions often reduces the file size, but the final size also depends on the format and encoder. Check the actual result comparison.
Can I resize without cropping?
Yes. Resizing keeps the full image. Use Crop Image separately when you want to remove areas around its edges.
Can this enlarge a small image or make it sharper?
No. This MVP supports retaining or reducing dimensions and does not include upscaling or image enhancement.