Compress an image

How to compress image

1. Add your images. One or many. Any common format including HEIC.
2. Set a target. Either a maximum file size, or a quality level directly.
3. Compare and download. Before and after sizes are shown for every image.

About compress image

Most image compression is done under a constraint rather than for its own sake. A job application wants a photo under 2 MB. A government portal caps uploads at 500 KB. An email will not send. A forum rejects anything over a megabyte. The requirement is a number, and the usual approach — dragging a quality slider, exporting, checking the size, repeating — is guesswork that takes several rounds.

So this tool works from the number instead. Give it a target size and it searches for the highest quality that fits, using a binary search across quality settings and, if necessary, reducing the dimensions. That converges in a handful of attempts and lands just under your limit rather than far below it, which matters because every kilobyte you leave unused is quality you gave away for nothing.

If you would rather control it directly, quality mode does that. Around 85 percent is visually indistinguishable from the original for photographs. Around 70 is where compression artefacts begin to appear in smooth areas — skies, walls, skin. Below 50 the image is noticeably degraded. The preview shows both versions so you can judge rather than trust a number.

Two things worth knowing about what compression can and cannot do. Dimensions usually matter more than quality: a 4000-pixel-wide photograph displayed in a 600-pixel column is carrying about forty times more data than it needs, and resizing it will beat any amount of quality tuning. And already-compressed images have little left to give — running a small JPEG through again mostly adds artefacts rather than saving space. The tool tells you when the output would be larger than the input rather than letting you save a worse file.

Common upload limits

Compress Image FAQ