Picocrypt [verified] -

It is free. It is auditable. It fixes bitrot. It uses gold-standard algorithms. And it fits on a floppy disk (metaphorically).

The entire application builds into a single standalone binary that generally hovers around in size. It requires absolutely no background services, network privileges, or administrative/root rights to execute on a computer. You can drop the executable straight onto a USB thumb drive and run it natively on any machine. 2. Drag-and-Drop Simplification picocrypt

Picocrypt also includes a variety of other useful features commonly found in more complex encryption suites. These include: It is free