Best Windows Free Open-Source Security Software

Private, end-to-end encrypted messaging.

A note-taking app with a focus on security and simplicity

Simple vaultless password manager in Go

Free backup software to store encrypted backups online

A simple, fast, and secure note-taking app

Cross-platform password manager compatible with Keepass 2.x

A secure password manager for teams

Fast, secure, efficient backup program

Fast and secure backup and versioning for files and directories

Secure, fast file transfers from the command line

Lightweight Intranet Penetration Proxy Server

Interactive, scriptable man‑in‑the‑middle proxy for HTTP, HTTPS and WebSocket traffic

General purpose TLS and crypto library

Open-source antivirus engine for detecting malware across platforms

High-performance reverse proxy for NAT traversal

An open platform for various uses

Secure dotenv for developers

A modern, secure password manager

A fast, secure, minimalist note‑taking app for students and freelancers

Secure, private budgeting for individuals and households

Stateless password manager