Guides
Plain answers to archive problems, from the people who built a zip tool that never uploads your files.
Why your ZIP file says it is corrupted, and how to fix it
Most "corrupted" ZIP files are not corrupt at all — they are a different format wearing a .zip name. Here is how to tell which problem you have.
How to open .rar files on a Mac
macOS cannot open .rar archives on its own. Here are the options that work, and how to check whether your file is really a RAR at all.
What is a zip bomb?
A zip bomb is a small archive that expands to something enormous. Here is how the trick works, and how to see the expansion before you extract anything.