SamCalculator

Pokemon Damage Calculator

Calculate Pokemon battle damage, KO chances, stat modifiers, STAB, type effectiveness, weather, abilities, items, and battle conditions — all on one page.

Battle settings

Examples:
sets both

Attacking Pokemon

FireFlying
Gen IX
EV
EV
IV

Defending Pokemon

GrassPoison
EV
EV
EV
IV

Move details

Fire
BP

Field conditions

Battle effects

Set up the attacker, defender, move, and conditions, then press Calculate Damage to reveal the damage range, KO chances, type effectiveness, and battle insights.

What is a Pokemon damage calculator?

A Pokemon damage calculator turns a battle setup — the attacking Pokemon, its move, the defender, and every field condition — into the exact damage range a hit will deal and the odds of a knockout. Instead of guessing whether your Earthquake secures the KO or leaves the opponent with a sliver of HP, you get a precise minimum-to-maximum damage spread, the percentage of the target's HP removed, and the chance to OHKO, 2HKO, or be survived.

This tool models the full main-series damage formula: base stats scaled by level, nature, EVs, IVs, and stat stages; STAB; the complete 18-type effectiveness chart; critical hits; weather and terrain; held items; abilities; screens; and status conditions like burn. It works the way competitive players plan in Pokemon Showdown and VGC team-building — letting you test what-if scenarios, compare attackers, and build a set that wins the damage race before the battle ever starts.

How Pokemon damage is calculated

Base damage from stats and power

The formula starts with ((2 × Level ÷ 5 + 2) × Power × Attack ÷ Defense ÷ 50) + 2. It uses the attacker's effective Attack (or Special Attack) against the defender's matching defensive stat, so higher offensive stats and stronger moves push the base number up before any multipliers apply.

The modifier chain

Base damage is then multiplied, in a fixed order, by targets, weather, critical hit, the random roll, STAB, type effectiveness, burn, and an 'other' bucket of items, abilities, and screens. Each step rounds a specific way, which is why two near-identical sets can land just above or below a key KO threshold.

The 85–100% damage roll

Every hit is multiplied by a random factor from 0.85 to 1.00 in 16 equal steps. That's why damage is always shown as a range: the lowest roll is 85% of the highest. KO chances come from how many of those 16 rolls — across one or more hits — are enough to reduce the target to zero HP.

Type effectiveness and STAB

The move's type is checked against both of the defender's types and multiplied together, giving 0×, ¼×, ½×, 1×, 2×, or 4×. If the move shares a type with the attacker it gets Same-Type Attack Bonus (STAB), normally 1.5× — the two single biggest swings in most damage calculations.

3 ways to use this calculator

1

Plan KOs before you attack

Set up the matchup and read the KO chance: a guaranteed OHKO, a roll-dependent 2HKO, or whether the target survives. Plan your turn around the odds instead of hoping the high roll shows up.

2

Build and tune EV spreads

Test how Attack or Special Attack investment, a boosting nature, and Choice or Life Orb items change your damage output — and how much Defense or HP a wall needs to survive a key hit.

3

Compare attackers and conditions

Use the team comparison and what-if controls to pit up to three attackers against one defender, or flip the weather, terrain, screens, and abilities to see exactly how much each one shifts the result.

Battle mechanics explained

STAB (Same-Type Attack Bonus)

When a Pokemon uses a move matching one of its own types, the move's damage is multiplied by 1.5× (2× with the Adaptability ability). A Charizard's Fire-type Flamethrower gets STAB; its Dragon Claw would not. In Gen IX, Terastallizing can add or shift STAB.

Type effectiveness

Each move type is strong, weak, or neutral against each defending type. Against a dual-type Pokemon the two multipliers multiply: Electric is 2× on Water and 2× on Flying, so Thunderbolt hits a Water/Flying Gyarados for a brutal 4×.

Physical vs Special

Physical moves use the attacker's Attack against the defender's Defense; special moves use Special Attack against Special Defense. The move — not its type — decides the category, so picking the side your Pokemon is strong on matters enormously.

Critical hits

A critical hit ignores the defender's positive defense stages and the attacker's negative offense stages, then multiplies damage by 1.5× (2× before Gen VI). Crits also bypass Reflect and Light Screen.

Weather

Sun boosts Fire moves by 50% and weakens Water by 50%; Rain does the reverse. Sandstorm raises Rock-types' Special Defense and Snow raises Ice-types' Defense, indirectly cutting the damage they take.

Terrain

Electric, Grassy, and Psychic Terrain boost their matching move types for grounded Pokemon (1.3× in Gen VIII+, 1.5× before). Misty Terrain halves Dragon-move damage to grounded targets.

Abilities

Abilities reshape damage in both directions: Adaptability and Technician raise output, while Multiscale, Filter, Thick Fat, and type-absorbing abilities like Levitate cut or cancel incoming hits entirely.

Held items

Choice Band and Choice Specs multiply the relevant attacking stat by 1.5×, Life Orb adds 30% at the cost of recoil, and Expert Belt rewards super-effective hits. On defense, Assault Vest and Eviolite boost the matching defensive stat.

Nature, EVs and IVs

Effort Values (up to 252 per stat), Individual Values (0–31), and a 10%/-10% nature shape the final stats the formula uses. A maxed, boosting-nature attacker can out-damage an uninvested one by well over 50%.

Damage rolls

The 0.85–1.00 random factor splits every hit into 16 possible damage values. 'Min damage' is the worst roll, 'max damage' the best, and 'average' the mean — the spread is exactly 15% wide before rounding.

Damage calculation best practices

  • Always set the defender's real EV spread — a wall with maxed HP and the relevant defense survives hits that a neutral 0-EV target would not.
  • Check both the minimum and maximum roll: a 'likely OHKO' that only KOs on 50% of rolls is a gamble, while a guaranteed KO uses the minimum roll.
  • Match the generation to the game you're playing — critical hits are 1.5× from Gen VI on but 2× in Gen II–V, and terrain boosts dropped from 1.5× to 1.3× in Gen VIII.
  • Remember STAB and type effectiveness stack: a 4× super-effective STAB move can deal six times a neutral non-STAB hit of the same base power.
  • In doubles, spread moves lose 25% of their power, and screens reduce damage by about a third rather than a half — set the format correctly.

Why damage calculation matters

In competitive Pokemon, almost every decision comes down to a damage calculation. Whether you switch, attack, set up, or protect depends on a single question: does this move KO, and does theirs KO me? Getting that answer wrong — assuming an OHKO that turns out to be a 2HKO — can lose the game on the spot, because the turn you spend not finishing a threat is a turn it spends sweeping your team.

Damage in the main series is deterministic apart from the 85–100% roll, the critical-hit chance, and a few secondary effects. That means a calculator can tell you the exact range and the precise KO odds for any setup. Team-builders use this to choose EV spreads that survive specific threats, to pick the item or nature that crosses a KO threshold, and to know before the battle whether a matchup is winnable. The maths rewards preparation, and this tool puts that preparation a few clicks away.

Core damage formulas

Base damage

((2 × Level ÷ 5 + 2) × Power × A ÷ D ÷ 50) + 2

A is the attacker's effective Attack or Sp. Atk; D is the defender's Defense or Sp. Def. Each division floors to a whole number before the next step.

Final damage

Base × Targets × Weather × Crit × Roll × STAB × Type × Burn × Other

The modifiers apply in this order, each with its own rounding. 'Other' covers items, abilities, screens, Helping Hand, and Friend Guard.

Stat formula (Gen III+)

⌊(⌊(2×Base + IV + ⌊EV÷4⌋) × Level ÷ 100⌋ + 5) × Nature⌋

Nature is 1.1, 1.0, or 0.9. HP uses a separate formula that adds Level + 10 instead of applying a nature.

Type effectiveness

Type = mult(move, type1) × mult(move, type2)

Each matchup is 0, 0.5, 1, or 2; multiplying two of them gives the 0× to 4× range you see against dual-type Pokemon.

STAB

1.5× (2× with Adaptability)

Applied when the move's type matches one of the user's types. Tera STAB in Gen IX can push this to 2× or even 2.25×.

KO chance

P(roll₁ + … + rollₙ ≥ target HP)

Across n hits and 16 equally-likely rolls each, the calculator counts the fraction of outcomes that reduce the target to zero HP.

Common damage calculation mistakes

1

Ignoring the defender's EVs

Calculating against a 0-EV defender massively overstates your damage. Real walls invest heavily in HP and a defense; always enter the spread you actually expect to face.

2

Confusing physical and special

A move's type does not set its category. Psyshock is Psychic but hits Defense, not Special Defense. Trust the move's category, not its type colour.

3

Reading the high roll as guaranteed

Max damage is one of 16 outcomes. A KO that needs the top roll happens only ~6% of the time per hit — look at the minimum roll for anything you must rely on.

4

Using the wrong generation

Crit multipliers, terrain boosts, and even the type chart have changed over time. A Gen V calculation will not match a Gen IX battle — set the generation first.

How accurate is this calculator?

This calculator uses the published main-series damage formula and the full Gen VI+ type chart, the same maths documented on Bulbapedia and used by competitive damage calculators. Stats are derived from the standard Gen III+ formula, the 16-value damage roll is modelled exactly, and KO percentages come from the true probability distribution of those rolls across multiple hits rather than a rough estimate.

Pokemon battle mechanics vary between game generations, formats, and official updates, and a few edge cases — residual healing, weather chip between turns, form changes, and certain niche abilities — are simplified or left out. Treat the output as an accurate planning estimate rather than a guarantee of any single in-game outcome. This is an independent fan tool and is not affiliated with, endorsed by, or sponsored by Nintendo, Game Freak, or The Pokemon Company.

Frequently Asked Questions

It recreates the game's damage formula. You enter the attacking Pokemon, its move, the defending Pokemon, and the battle conditions, and the calculator works out each Pokemon's effective stats from level, nature, EVs, IVs, and stat stages, then runs the base-damage formula and applies every multiplier in order — targets, weather, critical hit, the random roll, STAB, type effectiveness, burn, items, and abilities. Because each hit has 16 possible damage rolls, the result is shown as a minimum-to-maximum range with a percentage of the target's HP and the probability of a knockout.

STAB stands for Same-Type Attack Bonus. When a Pokemon uses a move that shares one of its own types, the move deals 1.5× damage. For example, a Fire/Flying Charizard gets STAB on Flamethrower (Fire) and Air Slash (Flying), but not on Dragon Claw. The ability Adaptability raises STAB to 2×, and in Generation IX Terastallizing into a type can grant or shift STAB, sometimes stacking to 2× or 2.25×. STAB is one of the largest multipliers in the formula, which is why most competitive Pokemon are built around strong same-type moves.

A critical hit multiplies damage by 1.5× in Generation VI onward (it was 2× in Generations II–V). Crucially, a crit also ignores any defensive stat boosts on the target and any offensive stat drops on the attacker, and it bypasses Reflect and Light Screen. By default moves have about a 1-in-24 chance to crit, raised by high-critical-ratio moves, items, and abilities. In this calculator you can toggle a critical hit on to see the boosted damage and compare it against the normal hit.

A lot stacks together: the attacker's level and effective Attack or Special Attack, the move's base power and category, the defender's Defense or Special Defense and its HP, STAB, type effectiveness, critical hits, the 85–100% random roll, weather, terrain, held items, abilities, screens like Reflect and Light Screen, status conditions such as burn, and stat stages from moves like Swords Dance. Natures, EVs, and IVs feed into the stats before any of that. This calculator lets you set each factor so the output reflects the exact scenario you care about.

Type effectiveness is how strong a move's type is against the defending Pokemon's type(s). Each matchup is super effective (2×), neutral (1×), not very effective (0.5×), or no effect (0×). Against a dual-type Pokemon the two multipliers multiply together, producing 0×, 0.25×, 0.5×, 1×, 2×, or 4×. A classic example is Electric against a Water/Flying Gyarados: 2× for Water and 2× for Flying gives a devastating 4×. The calculator reads both of the defender's types automatically and shows the combined multiplier.

Harsh sunlight boosts Fire-type move damage by 50% and weakens Water-type moves by 50%; rain does the opposite, boosting Water and weakening Fire. Sandstorm and Snow don't change move power directly but raise the Special Defense of Rock-types and the Defense of Ice-types respectively, which lowers the damage those Pokemon take. Weather also powers up weather-dependent moves and abilities. Set the weather in the field conditions section and the calculator applies the correct multiplier automatically.

Effort Values (EVs) are training points — up to 252 in a single stat and 510 total — that raise a Pokemon's stats at level 100 by up to 63 points in one stat. Investing EVs in Attack or Special Attack directly increases offensive output, while EVs in HP, Defense, or Special Defense let a defender survive bigger hits. Combined with a helpful nature and perfect IVs, full offensive investment can raise your damage by more than 50% over an untrained Pokemon. Enter the EVs for both Pokemon to get an accurate result.

Every hit is multiplied by a random factor between 0.85 and 1.00, split into 16 equally likely values. This is why damage is always a range rather than a single number — the lowest roll deals 85% of what the highest roll deals. The calculator shows the minimum, maximum, and average damage, and bases its knockout percentages on how many of those rolls (across one or more hits) are enough to faint the target. A 'guaranteed' KO works even on the minimum roll; a 'likely' KO depends on getting a higher one.

Yes, many abilities change damage. On offense, Adaptability raises STAB to 2×, Technician boosts weak moves, Iron Fist and Tough Claws power up punching and contact moves, and Huge Power doubles Attack. On defense, abilities cut or cancel damage: Multiscale halves hits at full HP, Thick Fat resists Fire and Ice, Filter and Solid Rock soften super-effective hits, and Levitate, Flash Fire, Water Absorb, and Volt Absorb give full immunity to a whole type. Select the relevant ability for each Pokemon to factor it in.

The calculator covers the main-series games from Generation I through Generation IX, with the latest generation selected by default. The generation selector adjusts mechanics that have changed over time, such as the critical-hit multiplier and terrain boosts. The type chart uses the modern Generation VI+ values, including the Fairy type. Damage is calculated for the standard main-series formula, so it lines up with games like Scarlet & Violet, Sword & Shield, and the simulation used by Pokemon Showdown, rather than spin-offs like Pokemon GO, which use a different system.

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