BIRCH TREE STUDIO

Birch Sliver

Smaller, sealed, and yours.

The simplest way on a Mac to make your important files smaller and truly private — even the ones other tools can't shrink.

Coming soon to the Mac App StoreQuestions? Support →

Dead simple

Drag a file in, pick a passphrase, done. Birch Sliver compresses it and seals it in one move, and hands you back a single .sliver file. To open it, drop it back in and type your passphrase. No settings to wade through, no manual to read — it does the obvious thing and gets out of your way.

Truly private

Everything happens on your Mac. Birch Sliver has no account, no sign-in, and no network access at all — it literally can't send your files anywhere, even if it wanted to. Nothing is uploaded, nothing is scanned, nothing leaves your device. Private isn't a checkbox here; it's how the app is built.

Shrinks what others can't

On the stuff that actually compresses — documents, code, logs, notes — Birch Sliver routinely beats a plain zip. And here's the part other archivers can't do: it shrinks your photos too, losslessly. Same JPEG, every pixel intact, just smaller. Most tools shrug at an already-compressed file; Birch Sliver finds the room they miss.

And it never makes a file bigger

We'll always be straight with you. Some files — video, music, already-zipped archives — are already about as small as they'll ever get, and no tool can change that. When that's the case, Birch Sliver says so plainly and seals the file as-is. It never pads a file out to look busy, and it never makes anything bigger than it needs to be.

Good to know

The honest details live on two short pages: what you can and can't do in support (including the big one — a lost passphrase can't be recovered, by design), and exactly how your data is handled in privacy (short version: nothing is collected, nothing leaves your Mac).