Image Resizer
Resize, crop and rotate images with pixel-perfect control — by exact dimensions, a percentage, or a preset size, with high-quality Lanczos resampling. Everything runs in your browser; your files are never uploaded.
Tip: paste with Ctrl/⌘ + V · everything is processed on your device — nothing is uploaded.
How to resize an image online
- 1
Drop, browse, or paste an image (PNG, JPG, WebP, HEIC or BMP).
- 2
Optional: turn on Crop, pick an aspect ratio and drag the box — or rotate and flip the image.
- 3
Resize by percentage, exact dimensions, or a preset size; keep "Lock aspect ratio" on to keep proportions.
- 4
Choose a resampling method (Lanczos is sharpest), a fill mode, and add sharpening if you upscaled.
- 5
Pick an output format and quality (or PNG color depth), then download — the new size updates live.
About the Image Resizer
Resizing images is one of the most common tasks on the web — shrinking a photo so it uploads faster, fitting an image to exact dimensions for a website or social post, or scaling artwork up. iResize gives you pixel-perfect control with high-quality Lanczos resampling, aspect-ratio locking, fit modes and live previews. Because it runs entirely in your browser there are no upload limits and your photos stay completely private.
Frequently asked questions
Are my images uploaded to a server?
No. All resizing happens locally in your browser using the Canvas API. Your files never leave your device, so it is completely private.
Which image formats are supported?
You can resize PNG, JPEG, WebP and BMP images, and export to PNG, JPEG or WebP.
Will resizing reduce the quality of my image?
Making an image smaller keeps quality high. Enlarging beyond the original size can soften details, since no new pixels can be invented. For JPEG and WebP you can also choose an output quality.
Is there a file-size limit?
There is no fixed limit, but very large images depend on your device's memory. Most photos resize instantly.
Does it keep the aspect ratio?
Yes. Aspect-ratio lock is on by default, so changing the width updates the height automatically. You can turn it off to stretch freely.