How to Compress an Image Online Without It Looking Compressed

A 4MB photo doesn't need to be 4MB to look good on screen. Most of that size is color information your eyes can't actually distinguish — compression finds and removes it, often cutting file size by 80-90% with no visible difference at normal viewing size.

What a quality slider is actually doing

JPG and WebP compression work by discarding fine color and detail variation the human eye is least sensitive to — not by shrinking the image or cutting quality evenly across the board. At high quality settings, almost nothing you'd notice is removed. Push the slider low enough and you start to see it: blocky artifacts around sharp edges, and smearing in areas that were fine gradients. The right setting is the lowest one where you genuinely can't tell the difference — which varies by image, so it's worth comparing before committing.

Why this tool doesn't take PNG files

PNG uses lossless compression by design — there's no quality slider to speak of, because PNG never throws detail away in the first place. That makes a JPG/WebP-style compressor the wrong tool for a PNG: there's comparatively little left to gain. If a PNG is too large, converting it to WebP (which supports both lossless and much more aggressive lossy modes) usually shrinks it far more than any PNG-specific optimization would.

How to compress an image

1. Open the Image Compressor and add one or more JPG or WebP images.
2. Pick a quality level and check the estimated before/after file size.
3. Download the compressed image, processed entirely on your device.

When compression alone isn't enough

If the file is still too large after compressing at a quality you're happy with, the image is probably larger than it needs to be in pixel dimensions too — shrink it first with the Image Resizer, then compress what's left. And if you're starting from a PNG, converting to WebP first usually beats compressing the PNG directly.