Risk Dice Calculator

Risk Dice Combat Calculator

function rollDie() { return Math.floor(Math.random() * 6) + 1; } function simulateCombatRound(attackerDiceCount, defenderDiceCount) { var attackerRolls = []; for (var i = 0; i < attackerDiceCount; i++) { attackerRolls.push(rollDie()); } attackerRolls.sort(function(a, b) { return b – a; }); // Sort descending var defenderRolls = []; for (var i = 0; i defenderRolls[0]) { defenderLosses++; } else { attackerLosses++; } // Compare second highest dice, if both have enough if (attackerDiceCount >= 2 && defenderDiceCount >= 2) { if (attackerRolls[1] > defenderRolls[1]) { defenderLosses++; } else { attackerLosses++; } } return { attackerLosses: attackerLosses, defenderLosses: defenderLosses }; } function calculateRiskCombat() { var attackerDice = parseInt(document.getElementById("attackerDice").value); var defenderDice = parseInt(document.getElementById("defenderDice").value); var numSimulations = parseInt(document.getElementById("numSimulations").value); if (isNaN(attackerDice) || attackerDice 3) { document.getElementById("result").innerHTML = "Please select a valid number of attacker dice (1-3)."; return; } if (isNaN(defenderDice) || defenderDice 2) { document.getElementById("result").innerHTML = "Please select a valid number of defender dice (1-2)."; return; } if (isNaN(numSimulations) || numSimulations 1000000) { document.getElementById("result").innerHTML = "Please enter a valid number of simulations (100-1,000,000)."; return; } var totalAttackerLosses = 0; var totalDefenderLosses = 0; for (var i = 0; i < numSimulations; i++) { var roundResult = simulateCombatRound(attackerDice, defenderDice); totalAttackerLosses += roundResult.attackerLosses; totalDefenderLosses += roundResult.defenderLosses; } var avgAttackerLosses = totalAttackerLosses / numSimulations; var avgDefenderLosses = totalDefenderLosses / numSimulations; var resultHtml = "

Simulation Results (" + numSimulations + " rounds)

"; resultHtml += "On average, for each combat round:"; resultHtml += "Attacker loses: " + avgAttackerLosses.toFixed(2) + " armies"; resultHtml += "Defender loses: " + avgDefenderLosses.toFixed(2) + " armies"; document.getElementById("result").innerHTML = resultHtml; }

Understanding Risk Combat Odds

The board game Risk is famous for its strategic gameplay, but also for the pivotal role of dice rolls in determining combat outcomes. While strategy dictates where and when to attack, the dice decide the immediate fate of your armies. This Risk Dice Combat Calculator helps you understand the probabilities involved in a single combat round, allowing you to make more informed decisions.

How Risk Combat Works

In Risk, when an attacker invades a territory, both sides roll dice to determine losses. The rules are as follows:

• Attacker: Can roll up to 3 dice, but must have at least 2 armies in the attacking territory (1 army must remain behind). So, if you have 3 armies, you can roll 2 dice. If you have 4+ armies, you can roll 3 dice.
• Defender: Can roll up to 2 dice, but must have at least 2 armies in the defending territory. If they have only 1 army, they can only roll 1 die.

The highest attacker die is compared to the highest defender die. If the attacker's die is higher, the defender loses an army. If the defender's die is equal to or higher, the attacker loses an army.

If both sides rolled at least two dice, the second highest attacker die is compared to the second highest defender die using the same rules. This means in a single combat round, a maximum of two armies can be lost by each side.

Using the Calculator

Our Risk Dice Combat Calculator simulates thousands of combat rounds based on your input to give you an average outcome. Here's how to use it:

1. Attacker Dice: Select how many dice the attacker will roll (1, 2, or 3). Remember, this depends on the number of armies the attacker commits.
2. Defender Dice: Select how many dice the defender will roll (1 or 2). This depends on the number of armies the defender has in the territory.
3. Number of Simulations: Choose how many times the combat scenario should be simulated. More simulations lead to more accurate average results.
4. Calculate: Click the "Calculate Combat Odds" button to see the average number of armies lost by both the attacker and defender per combat round.

Interpreting the Results

The calculator provides the average losses for both the attacker and defender over many simulated rounds. For example:

• Scenario: Attacker rolls 3 dice vs. Defender rolls 2 dice (3 vs 2)

  Typically, the results will show the attacker losing around 0.97 armies and the defender losing around 1.03 armies per round. This indicates a slight advantage for the attacker in this common scenario.

• Scenario: Attacker rolls 2 dice vs. Defender rolls 1 die (2 vs 1)

  In this case, the attacker might lose about 0.58 armies, while the defender loses about 1.42 armies. This shows a much stronger advantage for the attacker when the defender has fewer dice.

These averages help you understand the inherent advantage or disadvantage in different dice matchups. While individual rolls are always random, knowing the long-term probabilities can guide your strategic decisions, such as when to press an attack or when to reinforce a territory.