Resize Image Online
Change width and height in pixels — aspect ratio locked, processed locally.
Original size:
How to resize image in 3 steps
- 1
Upload an image
Drop a photo into the box to load it instantly.
- 2
Enter new dimensions
Type a width or height in pixels. Keep the lock on to preserve proportions.
- 3
Download the resized image
Kotopig renders the new size locally — save it with one click.
Why use Kotopig?
Your files stay private
Images are processed on your device and never uploaded to any server.
Instant results
No upload or download queue — processing starts the moment you drop a file.
Free, no sign-up
No account, no watermarks on output, no per-day limits. Just open and use.
Frequently asked questions
Are my images uploaded to a server?
No. Every operation runs entirely inside your browser using your device's own processor. Your files never leave your computer, so the tool works even with the page disconnected from the internet after loading.
How do I resize without stretching?
Leave the 'lock aspect ratio' option on and enter just one dimension; the other is calculated automatically so the image never looks squished.
Can I make an image larger?
Yes, you can upscale, though enlarging beyond the original resolution can look soft. Kotopig uses high-quality smoothing to keep it as crisp as possible.
What size do I need for a profile picture?
Common avatar sizes are 400×400 or 512×512 pixels. Enter those values and keep the aspect ratio square by cropping first if needed.