← Pocketsize — compress images in your browser
Every image tool says it cares about your privacy. Almost all of them still send your picture to a server to do the work. Pocketsize does not — the compression runs inside your browser, on your own computer — and because that claim is worthless as words alone, this page shows you three ways to verify it, each in about a minute, none requiring any technical background beyond pressing a key.
Open Pocketsize, then press F12 (or
right-click the page and choose "Inspect") and click the
Network tab — this panel shows every single thing a
page sends or receives, and it cannot be fooled. Now drop a photo in
and compress it. What you will see: the page downloading its own
machinery (files ending in .js, .css,
.wasm) — and your photo appearing nowhere. No POST, no
upload, no request carrying your file. The panel stays silent because
there is nothing to send: the encoders themselves were downloaded to
your machine, and your picture never leaves it.
Not uploading is a choice; being unable to upload is a guarantee, and Pocketsize ships with the guarantee. Every page is delivered with a security header called a Content Security Policy that your browser itself enforces. Ours says, among other things:
default-src 'none'; connect-src 'self'; form-action 'none'
In plain words: this page may talk to its own address to fetch its own
files, and to nowhere else, ever. If the code tried to send your
picture anywhere — because of a bug, a compromise, or a change of
heart — the browser would block the attempt. You can
read this header yourself in the same Network panel: click the first
request, look under "Response Headers" for
content-security-policy.
The simplest proof of all. Visit Pocketsize once, then turn on airplane mode or pull the network cable — and keep compressing. The whole compressor, encoders included, keeps working with no connection at all, because after your first visit it lives on your device. A tool that uploaded your pictures could not do this.
Honesty cuts both ways, so here is the whole picture: like any website, the server that hands you the app sees the ordinary request for the app itself — the visit. It never sees your pictures, their names, their sizes, or anything about them, because no request carrying them is ever made. There are no analytics scripts and no third-party requests of any kind; the security policy above forbids those too.
Everything this page claims can be checked a fourth way: by reading
the code. Pocketsize is open source —
source & licence on GitHub — and the same
engine ships as a command line for folders and scripts:
pip install pocketsize.