Tailscale
Tailscale Inc. is a software company based in Toronto, Ontario. Tailscale develops a partially open-source software-defined mesh virtual private network and a web-based management service. The company provides a zero config VPN as a service under the same name.
History
Founded in 2019 by Google engineers Avery Pennarun, David Crawshaw, David Carney, and Brad Fitzpatrick, the company secured funding of $12 million in a Series A round in November 2020 led by Accel with seed investors Heavybit and Uncork Capital participating. In May 2022, the company secured a $100 million Series B round, led by CRV and Insight Partners, with participation from existing investors. In April 2025 the company secured a $160 million Series C round, led by Accel, with participation from CRV, Insight Partners, Heavybit, and Uncork Capital.The company's name is inspired from a research paper The Tail at Scale published by Google.
Software
The open-source software acts in combination with the management service to establish peer-to-peer or relayed VPN communication with other clients using the WireGuard protocol. Tailscale can open direct connection to the peer using NAT traversal techniques such as STUN or request port forwarding via UPnP IGD, NAT-PMP or PCP. If the software fails to establish direct communication it falls back to using DERP (Designated Encrypted Relay for Packets) protocol relays provided by the company. The IPv4 addresses given to clients are in the carrier-grade NAT reserved space. This was chosen to avoid interference with existing networks. The Linux client can also send traffic to networks behind itself by disabling SNAT and routing directly to the source IPs.Supported platforms
The Tailscale client software supports a number of operating systems and embedded software systems, including:A Kubernetes operator and Docker images are also available.