Two ways to compress
- Quality sets how much detail to keep. 80% is a good default: most people can't tell it apart from the original, and the file is usually a fraction of the size. Go lower for thumbnails, higher for photos you might print.
- Under a file size is for upload limits on forms, job and visa applications, and email. Enter the limit in KB (1 MB = 1024 KB) and the tool finds the highest quality that fits. If even low quality is too big, it reduces the dimensions step by step until it fits.
Most of the saving usually comes from the dimensions. A modern phone photo is around 4000 pixels wide, far more than a screen or a web page needs, so "Max width or height: 1920 px" alone often cuts the file to a quarter of its size.
JPG, PNG or WebP?
| Format | Best for | Watch out for |
|---|---|---|
| JPG | Photos that must open everywhere, email, forms | No transparency; sharp text and logos get fuzzy edges |
| WebP | Websites and online stores: usually noticeably smaller than JPG at the same quality | Some older software and upload forms don't accept it |
| PNG | Screenshots, logos, diagrams, transparent images | Large files for photos; quality setting doesn't apply |
Converting a transparent PNG to JPG fills the transparent parts with white.
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Good to know
- Hidden data is removed. Re-encoding drops EXIF data such as GPS location and camera details. To remove it without compressing, use the photo location remover.
- Photos stay upright. The phone's rotation setting is applied before compressing, so the result displays the right way round everywhere.
- Animated GIFs become a still image of the first frame.
- iPhone HEIC photos: convert them with the photo location remover first, which turns them into JPG.
FAQ
Why is my compressed file bigger than the original?
The original was already heavily compressed, or you converted to a less efficient format (for example a photo to PNG). Lower the quality, choose JPG or WebP, or reduce the dimensions.
Is there a limit on how many images?
No. Images are processed one at a time on your device, so big batches just take a little longer.