Pi-hole

Pi-hole is a network-level advertisement and internet tracker blocking application that acts as a DNS sinkhole, protecting all devices on a local network from ads, tracking domains, and known malicious websites without requiring any client-side software installation. Originally created by Jacob Salmela in 2014 to run on a Raspberry Pi single-board computer (hence the name), Pi-hole has since evolved into a powerful, production-grade network security tool that can be installed on any Linux system, Docker container, or even cloud VM. Unlike browser-based ad blockers like uBlock Origin, which only protect the browser where they are installed, Pi-hole operates at the DNS level: when any device on the network makes a DNS query for a known advertising or tracking domain, Pi-hole intercepts the query and returns a null response, effectively preventing the ad or tracker from loading. This means Pi-hole protects all devices on the network simultaneously, including smartphones, smart TVs, IoT devices, and gaming consoles that cannot run traditional ad blockers. Key features include: support for multiple upstream DNS providers (Google DNS, Cloudflare DNS, Quad9, OpenDNS, and custom servers), blocklist management with support for community-maintained and custom blocklists containing millions of domains, a web-based admin dashboard (pihole-web) showing real-time query statistics, top blocked domains, query types, and client activity, per-client and per-group blocking rules for fine-grained control over which devices see which blocks, a built-in DHCP server for automatic Pi-hole configuration of network clients, DNS-over-HTTPS (DoH) and DNS-over-TLS (DoT) support for encrypted upstream DNS queries, regex-based domain filtering for custom block and allow rules, and an API for programmatic access. As of 2026, Pi-hole has over 50,000 GitHub stars.