An image compressor shrinks a photo's file size by re-encoding it at a lower quality, trading a small amount of detail for a much smaller file. This one runs entirely in your browser using the canvas element, so the original file never leaves your device. You get back a smaller copy, and that's it.
How to use it
- Choose an image from your device.
- Drag the quality slider to set how much compression to apply.
- Watch the preview update as you move the slider.
- Compare the original size to the compressed size shown above the preview.
- Download the compressed version once it looks right.
- Try a different quality setting if it looks too soft or is still too big.
When it helps
- Shrinking photos before they go on a website, so the page loads faster.
- Getting a photo under an email attachment limit without cropping it.
- Reducing the size of a screenshot before sending it in a chat or a support ticket.
- Preparing product photos for an online store, where load speed affects sales.
- Freeing up space on a phone by shrinking a folder of old photos.
Good to know
- Start around 0.7. It usually cuts the file size a lot with barely noticeable loss of detail.
- Photos can take more compression than graphics with sharp text or lines, which show artifacts more easily.
- Check the result at full zoom before publishing, since compression artifacts that are invisible at thumbnail size can be obvious up close.
- Compress a copy of your image, not your only original. Always keep an uncompressed source in case you need to edit it further or compress it differently later.
- If you're preparing images for a portfolio site, compress a test image first and view it at the size it will actually display, since that's more telling than checking it at full resolution.
Questions
What formats does this accept?
JPEG, PNG, and WebP as input. It outputs a compressed JPEG, which is usually the smallest option for a photo.
Does compressing change the image dimensions?
No, only the quality encoding changes. Use the image resizer separately if you also need to change the pixel size.
Is there a file size limit?
Not a hard one, though a very large image will take a bit longer since everything happens in your browser.
Does compression remove metadata like camera settings?
Since the image is redrawn on a canvas and re-encoded, most embedded metadata like camera details gets stripped out, which can be a helpful privacy side effect.
Can I compress a PNG and keep it as a PNG?
This outputs a compressed JPEG, since JPEG generally achieves smaller sizes for photos. For lossless PNG specific compression, a dedicated PNG optimizer would fit better.
Why does a photo with a lot of fine detail compress less effectively?
Compression works by simplifying areas that repeat or don't change much. A photo with a lot of fine texture has less of that kind of redundancy, so it doesn't shrink as dramatically as a simpler image at the same quality setting.