Playerbase

Runs on: Minecraft 26.3 and 1.21 to 1.21.11 (Fabric); 1.21, 1.21.1, 1.21.3 to 1.21.5, 1.21.8, 1.21.10 and 1.21.11 (NeoForge); 1.20.3 and 1.20.4 (Fabric); 1.20, 1.20.1, 1.19.2 to 1.19.4 and 1.18.2 (Forge, Fabric). Server-side only, so vanilla players can join.

Are players coming back, or just passing through? Online counts tell you about tonight. Playerbase tells you whether last week's newcomers returned, which is the number that decides whether a server grows.

Drop one jar into mods/, start the server, open the link it prints. You get:

• Players today, split into new and returning, with yesterday for comparison
• D1 and D7 retention: of the players whose first visit was a day ago / a week ago, how many came back
• Returned in first week: the forgiving version of retention for smaller servers
• Peak online per day and all time, and joins by hour so you know when to schedule events
• Average session length, chat volume, and which languages your players use
• A recent players table with sessions, play time, first and last seen
• /playerbase in game for the headline numbers and the dashboard link (operators, or anyone in singleplayer)
• A JSON API (/api/summary, /api/players) for your own Discord bot or spreadsheet

Private by design. Everything is written to a plain text file in config/playerbase/ and served from the server itself on 127.0.0.1 with a random token. Nothing leaves your machine. No accounts, no telemetry, no third-party libraries in the jar.

Light on the server. Three event listeners and an append-only log. Stats are rebuilt from the log at startup, so a crash never corrupts a database.

INSTALL

1. Put the jar and Fabric API in your server's mods/ folder and start the server.
2. Read the dashboard URL from the server log (Playerbase dashboard: http://127.0.0.1:8765/?token=…) or run /playerbase in the console. The token is generated on first start and stored in config/playerbase/playerbase.properties.
3. To reach the dashboard from another machine, set http.bind=0.0.0.0 in playerbase.properties and put it behind HTTPS or an SSH tunnel. Keep the token secret.

SETTINGS (config/playerbase/playerbase.properties) http.enabled=true | http.bind=127.0.0.1 | http.port=8765 | http.token=(generated) | http.publicUrl= | data.retentionDays=90

FAQ Does it slow the server down? No measurable cost: it records a line of text when someone joins, leaves or chats. Where is the data? events.jsonl and playerbase.properties in config/playerbase/. Does it work with LuckPerms, Essential Commands, Styled Chat? It does not touch them; it only listens to join, disconnect and chat events. Is my players' data shared anywhere? No. Nothing is sent off the server.

Compatibility: Minecraft 26.3 with Fabric Loader 0.20.1 and Fabric API. Java 25. Server-side: runs on dedicated servers and on the integrated server in singleplayer; other players install nothing. Licence: MIT.

Found a bug or want a feature? Comment here and I will answer. Custom plugin work for servers is available on request.

Want to know which ad, video or server list brings players who actually stay? Playerbase Pro is the paid edition for Paper and Purpur 26.3 servers: join-source tracking (one subdomain per promotion), eight weekly retention cohorts, daily and weekly Discord reports and CSV export. One jar, no database, $7.49. Get it on itch.io: https://molonlav3.itch.io/playerbase-pro or on Ko-fi: https://ko-fi.com/s/0f2a202b53 . This free Fabric edition stays free.

Need something custom? I build small server plugins to order from $35 (fixes) and $90 (a new one-feature plugin): https://ko-fi.com/molonlav3/commissions . If this mod saved you time, a coffee helps keep the updates coming: https://ko-fi.com/molonlav3