How the image resizer works
Resizing draws your original image onto a canvas set to the new target dimensions, letting the browser handle the pixel resampling. With aspect ratio locked, changing width automatically recalculates height (and vice versa) using the original image's proportions:
New height = New width × (Original height ÷ Original width)
Step-by-step guide
- Choose an image file from your device.
- Enter your target width and/or height.
- Keep 'Lock aspect ratio' checked to avoid distorting the image, or uncheck it for an exact custom size.
- Download the resized image.
Common target sizes
| Use case | Typical size |
|---|---|
| Website hero image | 1920×1080px |
| Blog thumbnail | 800×450px |
| Social media profile photo | 400×400px |
| Email header | 600×200px |
Frequently asked questions
Only if you resize with 'Lock aspect ratio' unchecked to dimensions that don't match the original proportions. Keep the lock enabled to resize proportionally without distortion.
Yes, though enlarging an image beyond its original resolution will reduce sharpness, since no new detail is created — the browser interpolates existing pixels rather than adding real detail.
The download is saved as JPEG by default, which works for most photos. For images needing transparency, use our Image Format Converter to export as PNG or WebP instead.