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Pentago Online

The Pentago strategy game in your browser: play an AI with four difficulty levels or real players with ELO rankings

Version
v2.6.1
Released
28 April 2026
Platform
Web · desktop & mobile browsers
Price
Free
Status
Available

Website ↗

A game against the computer in progress The winning line of five highlighted on the board Interactive step-by-step guide on a real board Home page: play against the computer or online Game settings: difficulty, series length and move time

About

Pentago Online is a web platform for Pentago, the two-player strategy game where you place a marble and then twist one of the four quadrants of the board. The first player to line up five marbles wins. It is a non-commercial, educational platform built to help children develop their strategy and reasoning skills.

Play

  • Against the computer at four levels — Easy, Medium, Hard and Expert — in series of 1, 3, 5 or 7 games, untimed or with 15, 30 or 60 seconds per move
  • Online against real players in ranked or unranked matches with an ELO rating and a leaderboard
  • Private lobbies with join requests, friends, in-game chat with a profanity filter, player reporting and tournaments

Learn

  • An interactive step-by-step guide on a real board: place marbles, rotate quadrants, win
  • How to play, rules and strategy guides, and an FAQ

Under the hood

  • Server-side AI engine: iterative deepening with a transposition table, threat detection with forced blocking, up to 5-move search on Expert, and time management in timed games
  • Real-time multiplayer over sockets with synchronised animations for both players
  • Turkish and English with language-specific URLs, structured data for search, bot protection on sign-up, privacy mode (hide from rankings, appear offline, turn off chat)

Pentago is a registered trademark of Tomas Flodén. Pentago Online is an independent implementation and is not affiliated with or endorsed by the trademark holder.

Version history

  1. v2.6.1 stable
    • New-version notifications: changes are shown automatically after an update
    • A friendlier changelog
    • Notification panel works on mobile
  2. v2.6.0 stable
    • The AI now respects the move timer in timed games: smart time management spends 70% of the time thinking and keeps 15% in reserve
    • AI Server/Local indicator: a live badge on the game screen shows where the AI is running
    • Improved lobbies: they close automatically when the connection drops, and abandoned matches are decided after 60 seconds
    • Better user management and error detection in the admin tools
  3. v2.5.0 stable
    • Rich results in Google search: game, FAQ and page hierarchy sent as structured data
    • A unique title and description for every page (Turkish/English)
    • reCAPTCHA v3 bot protection: invisible verification on sign-in and sign-up
    • Winning-hand animation: a pointer shows the winning line of five
    • The win effect in online games is shown to both players at the same time
    • Theme picker moved to the navigation bar: switch themes in one click
    • Admin panel: reporting and infrastructure improvements
  4. v2.3.0 stable
    • Redesigned lobbies with join-request approval for safe matchmaking
    • Return to your active lobby from any page: the lobby notice is available everywhere
    • Online game animations synchronised: both players see the same effects at the same time
    • The AI can now compute on the server: faster, more reliable moves
    • Stronger SEO: canonical URLs, hreflang and permanent redirects
  5. v2.2.0 stable
    • Change your password from the profile page, with a strength indicator
    • Online and vs-computer statistics tracked separately
    • User interface improvements
  6. v2.1.0 stable
    • AI engine moved to the server: moves computed live over a socket connection, with worker threads so the main server never blocks
    • New Expert level: 5-move search depth, threat detection, forced blocking and post-rotation awareness
    • In the early game the AI only searches around the marbles on the board: faster answers, no wasted work
    • The move timer now applies to the AI too in timed games
    • Game source code protected
    • Infrastructure and SEO improvements
  7. v2.0.0 stable
    • Multilingual URLs: dedicated addresses per language such as /tr/rehber and /en/guide
    • Statistics for games against the computer, per difficulty (wins, losses, draws)
    • The AI runs in a Web Worker in the background, so the game never freezes
    • AI thinks about 40% faster with a transposition table and iterative deepening
    • The AI detects the opponent's threats and blocks them
  8. v1.8.0 stable
    • All pages available in Turkish and English
    • Privacy mode: hide from rankings, hide online status, turn off chat
    • Cookie consent and educational-purpose notice
    • Redesigned language picker: flags side by side, one-click switch
  9. v1.7.0 stable
    • Sign in with your e-mail address or username
    • Password strength indicator on sign-up

For update checks: latest.json and releases.json are always up to date.