# Connect Four Classic Connect Four (7×6). Drop pieces that fall by gravity; first to line up four horizontally, vertically or diagonally wins. Play against a heuristic AI, a hard alpha-beta AI, or a friend locally. > Canonical page: https://elysiatools.com/en/tools/connect-four - **Category:** Games - **Keywords:** connect four, connect 4, four in a row, alpha-beta, ai opponent, two players, strategy, game ## Overview Play the classic Connect Four game directly in your browser on a standard 7×6 grid, choosing between a heuristic AI, a challenging alpha-beta pruning AI, or a local friend. ## Inputs - **Opponent Mode** (select) - **First Player** (select) ## When to use - When you want to test your strategic thinking against a challenging alpha-beta pruning AI opponent. - When you want to play a quick, local two-player game of Connect Four with a friend on the same screen. - When you need a quick mental break or want to practice basic spatial reasoning and blocking tactics. ## How it works - Select your opponent mode, choosing between easy heuristic AI, hard alpha-beta AI, or local two-player mode. - Choose which player goes first, setting either Red (you) or Yellow (opponent) to make the opening move. - Click on any of the seven columns to drop your colored piece, which falls to the lowest available space due to gravity. - Take turns until one player aligns four of their pieces horizontally, vertically, or diagonally to win the game. ## Use cases - Practicing tactical board game strategies against a deep-searching alpha-beta algorithm. - Passing the time with a local friend using the shared-screen two-player mode. - Teaching children basic spatial planning, pattern recognition, and gravity-based mechanics. ## Frequently asked questions ### What is the difference between the Easy and Hard AI modes? The Easy AI uses simple heuristic evaluations for quick moves, while the Hard AI uses alpha-beta pruning to search multiple moves ahead for optimal play. ### Can I play this game with a friend on the same device? Yes, select the 'Two players (local)' option to take turns dropping pieces on the same screen. ### What are the dimensions of the game board? The game uses the standard Connect Four board size of 7 columns by 6 rows. ### How do you win a match? You win by being the first player to form a continuous line of four of your colored pieces horizontally, vertically, or diagonally. ### Can I choose who makes the first move? Yes, you can configure the first player option to start as Red (you) or let Yellow (the opponent) go first. ## Related tools - [Adaptive 12-Point Hidden Watermark](https://elysiatools.com/en/tools/adaptive-12-point-hidden-watermark): Add a subtle text watermark to one image or every supported image in a ZIP, at all, random, or chosen perimeter positions with automatic dark/light local contrast. - [Bulk Density & Porosity Calculator](https://elysiatools.com/en/tools/bulk-density-calculator): Bulk density and porosity for granular or porous materials. Three-way solver: pick the unknown (ρ_bulk, m, or V) and supply the other two. ρ_bulk = m/V_bulk. Optionally enter the true particle density ρ_true to compute porosity ε = 1 − ρ_bulk/ρ_true, plus relative density against water. 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