Resize Image
Resize a JPG, PNG or WEBP image to exact pixel dimensions or by percentage. Runs entirely in your browser.
Resize an image
Upload an image, choose pixel or percentage sizing, then download the resized result.
Drag & drop an image here, or click to browse
Supports JPG, PNG and WEBP.
Result
Original dimensions
0 × 0 px
New dimensions
0 × 0 px
File size
0 KB
Your image is processed locally in this browser tab using the Canvas API. It is never uploaded to Calcooo or any server.
How to use this tool
- Drag and drop an image into the box above, or click to browse and select one.
- Choose whether to resize by exact pixel dimensions or by a percentage of the original.
- Enter the width/height (or scale percentage) — keep "Lock aspect ratio" checked to avoid stretching.
- Press Resize image, then click Download resized image to save the result.
FAQ
Frequently asked questions
Is my image uploaded anywhere when I resize it?
No. Your image is resized locally using the Canvas API in your browser. It never leaves your device.
What's the difference between pixel and percentage mode?
Pixel mode sets an exact width and height in pixels. Percentage mode scales the original dimensions proportionally — for example, 50% halves both the width and height.
What does "lock aspect ratio" do?
When enabled, changing the width automatically recalculates the height — and vice versa — to keep the image's original proportions and avoid stretching.
Does resizing reduce file size too?
Usually yes, since fewer pixels means less data. But for maximum size savings, also try the Compress Image tool afterward.