8 guides published so far — more are added regularly.
The exact two-pass compression process this tool runs in your browser: what's lossless, what's lossy, the sanity checks that prevent a bad result, and why nothing is ever uploaded.
Practical ways to shrink a PDF, and why running compression in-browser via WebAssembly gets most of the benefit automatically without picking settings yourself.
What's lossless and what's lossy when a PDF is compressed: the difference between structural cleanup and image re-rendering, and how to tell which one your file went through.
Typical email attachment size limits and how to get a large PDF under them using in-browser compression — plus what to do when compression alone isn't enough.
This tool runs in the browser, so the same compressor works on Windows, Mac, iPhone, Android and Linux — what to expect on each, and the one thing that differs by device.
Most 'compress PDF online' tools upload your file to a server first. Here's what that means for sensitive documents, and a two-minute way to verify whether any tool actually does that.
Scanned PDFs typically compress 50-90% because of how scanners save pages. Here's why, what resolution actually matters for readability, and when to be more careful.
How the paid batch mode works: compress several PDFs in one pass, download them as a single ZIP, and restore access on another device with just your email.