Image Compressor

No. All compression happens entirely in your browser using the HTML5 Canvas API. Your images never leave your device, nothing is sent to any server.

You can upload any image format your browser supports (JPEG, PNG, WebP, GIF, BMP, etc.). For output, you can choose between JPEG, WebP, and PNG formats.

For most use cases, 70-80% quality offers an excellent balance between file size and visual quality. For photos where quality matters, use 85-95%. For web thumbnails, 50-60% works well.

Only if you set a Max Width smaller than the original image width. The compressor will scale the image down proportionally. Otherwise, the dimensions stay the same, only the file size is reduced.

PNG is lossless, so the quality slider does not apply to it. Photographs almost always come out smaller when saved as JPEG or WebP instead.

For photos on the web, yes. WebP is typically 25 to 35 percent smaller than JPEG at comparable quality and every current browser supports it.

No. Re-compressing an already lossy image adds artefacts without saving much. Always start from the original file.

Match the largest size the image is actually displayed at, then double it for high density screens. Anything beyond that is bytes nobody ever sees.