Compress an image for upload

Keep the pixels, lose the quality

The instinct when a file is too large is to make the image smaller. For documents that is usually the wrong move. Legibility depends on resolution: a 3000 pixel wide scan of a birth certificate stays readable at 70% JPEG quality, while the same page reduced to 800 pixels wide becomes hard to read no matter how high the quality.

So leave the longest edge at zero, which keeps the original dimensions, and let the quality search do the work. Only reduce dimensions if quality alone cannot get you under the limit.

Why this matters for immigration uploads

IRCC and most visa portals cap individual uploads at a few megabytes. A single page photographed on a recent phone can easily be 6 to 10 MB, so compression is not optional. Applicants often solve this by emailing the file to themselves to let a mail provider shrink it, which strips resolution unpredictably and can render a document illegible.

The privacy problem with compression websites

The files people need to compress for an immigration application are exactly the files you should be most careful with: passports, birth certificates, bank statements, police certificates. The standard model for an online compressor is to upload your file, process it on a server, and hand back a download link, which means your identity documents sit on someone else's infrastructure.

This tool does the same job using the canvas and JPEG encoder already built into your browser. There is no upload step and no server, so there is nothing to retain, leak or subpoena.