YaCy is a free, peer-to-peer, decentralised search engine. Instead of relying on a central server, YaCy peers each run a network node that crawls and indexes the web, sharing results with the whole peer network — meaning search results come from a community-controlled index with no single point of failure or central censorship.

Key Features

• Fully decentralised — No central server; the network is formed by user-run peers
• Distributed indexing — Each peer crawls independently and shares its index with the network
• Privacy friendly — Search requests are distributed and not tracked by a central provider
• Ranked results — Relevance ranking across a community-moderated index
• Intranet search — Index your own local network, files and documents
• Open protocol — Anyone can run a peer and contribute to the network

Why Use YaCy?

YaCy is unique in that it puts a genuinely decentralised search index in your hands. If you care about an internet search that is not dominated by a single company and want to contribute to a common, open index, running a YaCy peer is a practical way to take part — while also giving you a private intranet search tool.

Use Cases

• Privacy-focused community and decentralised web search
• Intranet / private network document indexing
• Contributing to an open, community-owned web index
• Educational demonstrations of peer-to-peer systems

Platform

Linux · macOS · Windows (Java-based)

Licence

GPL-2.0

Website

yacy.net