The best open source alternative to TeamViewer is RustDesk. If that doesn't suit you, we've compiled a ranked list of other open source TeamViewer alternatives to help you find a suitable replacement. Other interesting open source alternative to TeamViewer is Defguard.
TeamViewer alternatives are mainly Remote Desktop Software but may also be Authentication & SSO Providers or VPN & Secure Access Tools. Browse these if you want a narrower list of alternatives or looking for a specific functionality of TeamViewer.
Cross-platform remote desktop solution offering seamless control, file transfer, and screen sharing with robust security and customization options.

Rustdesk is a powerful, open-source remote desktop software that revolutionizes the way you connect to and manage computers from afar. Built with performance and security in mind, Rustdesk offers a comprehensive suite of features that cater to both individual users and businesses alike.
Key benefits of Rustdesk include:
Whether you're an IT professional managing a fleet of computers, a remote worker accessing your office machine, or simply helping a friend with tech support, Rustdesk provides a reliable, efficient, and user-friendly solution for all your remote desktop needs.
Looking for open source alternatives to other popular services? Check out other posts in the alternatives series and openalternative.co, a directory of open source software with filters for tags and alternatives for easy browsing and discovery.
Enterprise-grade open source VPN solution combining WireGuard with mandatory 2FA/MFA and integrated OpenID Connect SSO for secure remote access

defguard is a comprehensive remote access solution that brings true zero-trust security to WireGuard VPN. The platform stands out with its mandatory Multi-Factor Authentication (MFA) for every VPN connection, ensuring maximum security.
Key features include:
The solution has been thoroughly audited by ISEC security researchers and is trusted by companies like Prusa Research, Hostinger, and others. Being open-source and on-premise, defguard helps protect sensitive data while providing enterprise-grade features without vendor lock-in.