xwiki-platform

Free: XWiki Standard (the platform) is LGPL-2.1, self-hosted, no user cap: WYSIWYG editor, realtime collaborative editing (bundled since 16.2), page history, comments, rights management, sub-wikis, App Within Minutes structured apps, and the community extension repository (including LGPL LDAP and OpenID Connect authenticators). Free Confluence XML import via the LGPL contrib Confluence tools. Community forum support only. XWiki SAS lets open source projects use Pro apps free (no support) and gives NGOs 50% off.

Self-hosted: Java servlet app on Tomcat or Jetty with PostgreSQL, MySQL/MariaDB (or Oracle on Enterprise), or the official Docker image (xwiki:*-postgres-tomcat, -mysql-tomcat, -mariadb-tomcat). Monthly releases; XWiki recommends the previous cycle's stable line (17.10.x today) for production and 18.4.x for new installs wanting newer features.

Paid: XWiki Pro/Support, same price on XWiki Cloud or on-prem, billed yearly (3-year terms save 20%), prices in EUR excluding tax. Starter: EUR 309/year for 10 users (about $346) or EUR 772.50 for 25 (about $865), XWiki Cloud only, 25-user cap, no Pro apps. Basic: EUR 1,486.29/year for 25 users (about $1,665), EUR 5,796.84 for 100 (about $6,490), up to 1,000 users, adds Pro apps and LDAP/AD support. Business: from EUR 11,216.70/year for 250 users (about $12,560), adds vendor-supported OIDC/Entra ID/SAML, IP allowlisting and the Confluence migration toolkit. Enterprise: from EUR 33,990/year for 500 users (about $38,070), adds SCIM, AI integration (beta), Change Request and Replication. Individual Pro apps from EUR 95/year (about $106), priced by the wiki's total active-user tier. XWiki Cloud trial is 10 days, renewable twice (30 days total).