Risk Dice Roller
Roll dice for Risk battles with realistic 3D physics. In Risk, the attacker rolls up to 3 dice and the defender rolls up to 2. Compare the highest dice to determine casualties. This roller defaults to 3 dice for the attacker тАФ adjust the count for defender rolls.
Risk Combat Rules
In Risk, combat is resolved by dice. The attacker can roll up to 3 dice (must have at least 1 more army than dice rolled). The defender rolls up to 2 dice (must have at least as many armies as dice rolled). Compare the highest attacker die to the highest defender die, then the second-highest pair if both sides rolled 2+. The lower die in each pair loses one army. Ties go to the defender.
Risk Battle Probabilities
When the attacker rolls 3 dice vs. the defender's 2 dice: the attacker wins both comparisons 37.2% of the time, splits (each side loses one army) 33.6% of the time, and the defender wins both 29.3% of the time. Over many battles, the attacker has a slight mathematical edge тАФ which is why Risk rewards aggressive play with large armies.
Risk Strategy: When to Attack
Attack when you have a significant numerical advantage (3:1 or better). Always roll the maximum number of dice available тАФ rolling 3 attacker dice gives much better odds than rolling 1 or 2. As the defender, always roll 2 dice when possible because ties favor you. Concentrate your forces rather than spreading thin, and use continent bonuses to build up overwhelming armies.
Frequently Asked Questions
Why does the defender win ties in Risk?
Ties going to the defender is a game design choice that gives a defensive bonus. Without it, attackers would have an even larger mathematical advantage. The defender tie-break, combined with the defender's 2-dice limit, creates the strategic tension between attacking and defending in Risk.
What are the odds when attacking in Risk?
With 3 attacker dice vs 2 defender dice, the attacker has about a 37% chance of winning both comparisons, 34% chance of splitting, and 29% chance of losing both. Over many rolls, the attacker loses about 0.92 armies per defender army lost.
How do I use this roller for Risk?
Roll 3 dice for the attacker, then adjust to 2 dice and roll again for the defender. Compare the highest dice from each roll, then the second-highest pair. The lower die in each comparison loses one army. Ties go to the defender.