Why image compression matters
Images make up the majority of bytes downloaded by a typical web page — often more than HTML, CSS and JavaScript combined. A single un-optimised camera photo can be 6 MB or more, while the same photo compressed at 80% quality will be under 400 KB and look identical to the human eye. Multiply that across a dozen photos on a portfolio, a product gallery, or a blog post and the savings are dramatic: faster page loads, lower bandwidth bills, happier mobile visitors, and a real boost to your Core Web Vitals (in particular LCP, the metric Google uses as a ranking signal).
How this image compressor works
Under the hood the tool uses a battle-tested open-source compression engine running entirely in your browser via a Web Worker, so the main thread stays responsive even on bulk jobs. For raster formats (JPG, PNG, GIF, WebP) it decodes the image, optionally resizes it, and re-encodes with the quality and target format you pick. For SVG it runs a text minifier that strips comments, doctype declarations and redundant whitespace from the markup — pure string manipulation, no re-rendering required.
Lossy vs lossless compression
Lossless compression squeezes out only data the decoder doesn't need — repeated bytes, unused colour entries, redundant markup. Pixel values are preserved exactly, so the result is bit-for-bit identical to the original on screen. PNG and SVG support lossless workflows; the trade-off is that file size reductions are usually modest (often 10–30%).
Lossy compression goes much further by discarding information your eye is unlikely to notice — high-frequency colour detail, very small luminance variations, areas of nearly-uniform colour. JPG, WebP and AVIF were designed for this. With a quality setting between 70 and 85 you'll typically see file sizes drop by 50–90% with no perceptible quality loss. Push the slider lower for aggressive savings on thumbnails and previews; push it higher for archival masters and prints.
Choosing the right output format
For photographs and screenshots full of detail, JPG remains the safe default — it's universally supported and very efficient at quality settings of 75 and above. For photos on modern sites where bytes matter most, WebP is the better choice: it produces 25–35% smaller files than JPG at the same visual quality. Reserve PNG for graphics that need sharp edges, transparency, or pixel-perfect text — but if you don't need transparency, converting a PNG screenshot to WebP can shrink it by 80% or more.
Privacy by default
Because everything runs locally, none of your files ever touch our servers — there's no upload step, no temporary storage, and no analytics on the file contents. That makes this compressor safe to use for personal photos, screenshots of internal tools, draft client work, or anything else you wouldn't want sitting on a third-party server. The only thing we collect is anonymous tool-visit counts, the same as every other page on the site.