Image Resizer
Image Resizer: free, instant and private. Aspect ratio is always preserved — the image fits inside the box you give it without stretching.
How the Image Resizer works
The Image Resizer takes Choose file, Max width (px, optional), Max height (px, optional), Output format, Quality for JPG/WebP (%) and returns the answer instantly — no button to hunt for, no page reload. Aspect ratio is always preserved — the image fits inside the box you give it without stretching. Choosing a smaller output and a moderate quality usually cuts file size by 70–90%, which is exactly what email and form uploads want.
Enter your own numbers to replace the example values; the result panel updates as you type. Everything runs in this single page, so nothing you enter leaves your device.
Formula used
new size = original × min(maxW ÷ width, maxH ÷ height, 1)
| Symbol | Meaning |
|---|---|
| max width / max height | the box the image must fit inside |
| 1 | the cap that stops the tool from upscaling past your original |
Aspect ratio is always preserved — the image fits inside the box you give it without stretching. Choosing a smaller output and a moderate quality usually cuts file size by 70–90%, which is exactly what email and form uploads want.
Inputs used: Choose file, Max width (px, optional), Max height (px, optional), Output format, Quality for JPG/WebP (%).
Worked example
Run the tool above with your own file — the result is a direct download, so there are no numbers to show here.
Frequently asked questions
- What formula does the Image Resizer use?
- It uses new size = original × min(maxW ÷ width, maxH ÷ height, 1), where max width / max height is the the box the image must fit inside; 1 is the the cap that stops the tool from upscaling past your original.
- Is the Image Resizer free?
- Yes. There is no signup, no usage limit and no watermark — the generator runs entirely in your browser.
- How do I read the result?
- Aspect ratio is always preserved — the image fits inside the box you give it without stretching. Choosing a smaller output and a moderate quality usually cuts file size by 70–90%, which is exactly what email and form uploads want.
- Does the Image Resizer store or send my data?
- No. Every calculation happens locally in the page, so the numbers you type are never uploaded or logged.
- Does it work on a phone and offline?
- Yes — the page is a single lightweight file that adapts to any screen size. Once it has loaded it keeps working without a network connection.