Resize Image — Change Photo Dimensions
Last updated: 2026-06-25
Photos never leave your device · 100% client-sideResizing an image changes its width and height in pixels to fit a screen or upload spec.
With aspect ratio locked, the new height = original height × (new width ÷ original width), so the photo never gets distorted, and everything is processed in your browser.
Image Resizer Tool
How to use
- Select an image — Drag the image you want to resize, or upload it with the file picker.
- Enter dimensions — Enter the width or height you want in pixels. With keep aspect ratio on, the other side is calculated automatically.
- Check the preview — Review the new width, height and preview.
- Download — Click the download button to save the resized image.
How image resizing works
Resizing redraws the pixel grid of the original photo to fit a new width and height. When shrinking, the colors of several pixels are averaged together; when enlarging, interpolation estimates the in-between pixels and fills them in. That is why shrinking loses almost no quality, but enlarging can look blurry.
To keep the photo from being distorted, you should preserve the aspect ratio. The formula is:
new height = original height × (new width ÷ original width)
Recommended sizes by platform
| Use | Recommended size | Notes |
|---|---|---|
| Instagram square | 1080 × 1080 | 1:1 ratio |
| YouTube thumbnail | 1280 × 720 | 16:9 ratio |
| Blog body | width 800–1200 | keep height ratio |
| Profile picture | 400 × 400 | square recommended |
| Email attachment | width up to 1024 | smaller file size |
After resizing, to cut file size further use image compression. For format choice, see the WebP vs JPG vs PNG guide.
Frequently asked questions (FAQ)
Can I shrink an image while keeping the aspect ratio?
Yes. With the keep aspect ratio option on, entering a width automatically calculates the height at the same ratio so the photo does not get distorted.
What happens to quality if I enlarge an image beyond its original size?
Enlarging past the original fills in pixels that did not exist using interpolation, so the result can look blurry or soft. When possible, avoid scaling above the original size.
Are my photos uploaded to a server?
No. Resizing runs 100% inside your browser, and your photos are never uploaded or stored.
Can I resize by percentage?
Yes. Entering 50 in the percent field shrinks both width and height to half the original. Use whichever you prefer — pixel input or percentage.
Related tools & guides
Last updated: 2026-06-25