Image Compressor

What is the image compressor?

An image compressor reduces the file size of a photo or graphic so it loads faster and uses less storage or bandwidth. This tool does it entirely in your browser using the HTML canvas, which means your images are never uploaded — a real privacy advantage over server-based compressors. It is ideal for shrinking photos before emailing them, attaching to a form, or publishing on a website.

How it works

When you select an image, the tool draws it onto an off-screen canvas at its original dimensions (or a smaller size if you scale it down). It then re-encodes the canvas to JPEG or WebP at the quality level you choose with the slider. Lower quality discards more fine detail and colour precision, producing a smaller file; higher quality preserves more at the cost of size. Because re-encoding is lossy, the tool shows the before and after sizes so you can find the best balance for your needs.

Worked example

Load a 4 MB smartphone photo, set quality to 70% and export as JPEG. The re-encoded image typically drops to well under 1 MB with little visible difference on screen. Reduce the output dimensions to 50% as well and the file can fall below 300 KB — perfect for a fast-loading web page. You can compare the original and compressed previews side by side before downloading.