Image Compressor: how to use it

Large photos are the most common reason a form upload fails or a web page loads slowly. A phone photo can easily be 4 to 8 MB, while many portals accept only 200 KB to 2 MB. The Image Compressor shrinks a picture by re-encoding it at a lower quality, and it does this entirely inside your browser, so the photo never leaves your device.

Compression works by discarding detail the eye is least likely to notice. A moderate setting usually cuts the file to a fraction of its size with no visible change; an extreme setting produces blocky patches and smeared edges. The goal is to find the lowest quality you can accept, not the lowest number.

How to use the Image Compressor

1. Open the tool and choose a JPG, PNG or WebP image from your device, or drag it onto the upload area. Keep the file under about 40 MB for smooth performance.
2. Move the Output quality slider. It starts at 80%, which is a good first try for photos.
3. Press Process image. The tool shows the original size, the new size and the percentage saved.
4. Look at the preview. If text or faces look rough, raise the quality a little and process again.
5. Press Download result and save the smaller file.

Tips for better results

• For photographs, 70 to 85% is the sweet spot. Below 60% you will usually see artefacts around edges and in sky gradients.
• If you need to hit an exact limit such as 100 KB, process, check the size, and adjust the slider in steps of five until you are just under it.
• Resize first if the picture is much larger than you need. A 4000-pixel-wide photo shown at 800 pixels wastes most of its bytes; use the Image Resizer, then compress.
• Screenshots and graphics with flat colour and sharp text compress better as WebP or PNG than as heavily compressed JPEG.

A note about PNG files

PNG is a lossless format, so it has no quality setting to lower. To give you a real saving, this tool saves PNG input as WebP (or as JPEG if your browser cannot create WebP). WebP keeps transparency; JPEG does not, so transparent areas become white in that fallback. The tool tells you when this happens.

Frequently asked questions

Is my photo uploaded anywhere?

No. The image is decoded and re-encoded by your own browser. Nothing is sent to a server, which is why the tool also works for private documents.

Why did my file get bigger?

Files that are already well optimised can grow slightly when re-encoded. The tool will tell you when this happens. Lower the quality or keep the original.

Will metadata such as GPS location be kept?

The re-encoded file is drawn onto a fresh canvas, so camera metadata such as location tags is normally not carried over.

Open the Image Compressor →

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