Compress images online
Drag your photos in, adjust the quality, and see the before/after size.
100% private — your files are processed on your device and never uploaded to a server.
How it works
- 1
Upload your images
Drag one or more photos into the drop zone, in JPG, PNG or WEBP.
- 2
Adjust quality and size
Move the quality slider and, optionally, set a max width/height to shrink very large photos.
- 3
Download the result
See how much each file's size was reduced and download it.
How image compression works
This tool re-encodes your image, adjusting the lossy compression level (for JPEG and WebP) and, optionally, reducing its maximum dimensions. The lower the quality value, the smaller the file — but also the more visible the loss of detail in high-contrast areas or text.
PNG is a lossless format: it has no real "quality" knob, so compressing it as PNG barely reduces its size. If your goal is to minimize file size, choose WebP as the output format — it keeps good visual quality with noticeably lighter files, even preserving transparency if the original image had it.
Frequently asked questions
How much can I shrink an image without it being noticeable?
It depends on the photo, but 70-85% quality is usually practically indistinguishable to the eye for typical photographs, with 40-70% size reductions.
Why does PNG barely shrink at all?
Because PNG is a lossless format — it has no quality control to trade detail for size. Choose WebP or JPEG as the output if you need a smaller file.
Does compression affect the image resolution?
No, unless you also enable the max width/height limit. Quality only controls how much visual information is discarded, not the pixel dimensions.
Are my photos uploaded to a server to compress them?
No. The whole process happens in your browser using the Canvas API. Your files never leave your device.