How to optimize images for the web
Format, dimensions and quality: the right order to cut file size without losing sharpness.
Image resizer
Change pixel dimensions while keeping the aspect ratio.
Runs in your browser
JPG, PNG, WebP, GIF, BMP or AVIF up to 30 MB. Processed on your device.
Choose an image to get started.
The image is never uploaded: it's processed with your browser's Canvas API.
What it does: Image resizer
Set the width and height of an image for a website, social media, a size-limited form or a presentation. The aspect ratio is kept by default so the image doesn't get distorted.
Downscaling happens in steps with high-quality smoothing to keep things sharp, and everything runs in your browser.
How to use it
- Choose or drag in the image.
- Enter the new width (the height is calculated for you) or a percentage.
- Pick the output format and press Resize.
- Check the preview and download the image.
Examples
Blog featured image
A 6000 × 4000 px photo resized to 1200 px wide becomes 1200 × 800 px, enough for most themes.
Photo for a form
If you're asked for at most 600 × 600 px, only untick “Keep aspect ratio” if the image is already square — otherwise it will be distorted.
Limits, formulas and assumptions
- Maximum output side: 10,000 px, and at most 16.7 megapixels so it also works on phones.
- Enlarging an image doesn't add detail; it only makes it bigger and blurrier.
- Resizing discards EXIF metadata.
Frequently asked questions
Do I lose quality when shrinking?
You lose pixels, but if the final size suits where it will be shown, you won't notice. Use PNG to avoid any extra compression loss.
What does keeping the aspect ratio mean?
Width and height change by the same factor, so the image isn't stretched or squashed.
Can I resize several at once?
One at a time for now. Processing is local, so it's quick even with large photos.
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