Pokémon Damage Calculator
Loading the damage engine…
Attacker
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Defender
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Choose an attacker and a defender to see the damage.
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Choose an attacker and a defender to see the damage.
A damage roll in Pokémon is not one number. Every hit multiplies by a random factor between 0.85 and 1.00 in sixteen equal steps, so the honest answer to "how much does this do" is a range and a probability. That is what the result line gives you: the lowest and highest rolls as a percentage of the target's health, and then the sentence that actually matters — whether it is a guaranteed knockout, a chance, or not happening.
Guaranteed OHKO means the lowest roll still kills. Possible means some rolls kill and some do not, and the percentage is how often. A 50% chance to knock out is a coin flip you may not want to take when losing it costs you the game.
Experienced players do not calculate every turn — they calculate once, remember the answer, and play off it for the rest of the season. The questions worth answering ahead of time are narrow and specific:
The maths is Smogon's own damage calculator, the same engine the competitive community has used for years, running here in your browser. It handles abilities, held items, weather, terrain, screens, stat boosts, critical hits and the mechanics of Pokémon Champions including Mega Evolution.
It does not know what your opponent is running. Every calculation assumes what you tell it, and the most common mistake is assuming an opponent has no investment when the ladder average says otherwise. If you are building for a format, calculate against the spread that beats you, not the one that makes your number look good.
Three numbers do the work. The range tells you the spread. The percentage tells you how much of the target's health goes. The verdict converts both into a decision. Everything else on the page exists to make those three honest.
A last habit worth borrowing: calculate the defensive case first. Knowing what survives is worth more than knowing what kills, because surviving is what gives you another turn to find out.
Every hit is multiplied by a random factor between 0.85 and 1.00 in sixteen steps. The calculator shows the lowest and highest of those sixteen rolls.
Even the lowest of the sixteen damage rolls knocks the target out. A “possible OHKO” means only some rolls do, and the percentage tells you how many.
Yes. Mega forms are selectable and their stats, typings and abilities are used. Pokémon Champions has no Terastallization, so no Tera control is offered.
It is the same open-source damage engine, @smogon/calc, running in your browser. Nothing is sent to a server.
Set the attacker to the threat you are worried about, then raise the defender’s HP and defence until the verdict stops saying it dies. That is the minimum you need; anything beyond it is spent elsewhere.