How CP Is Calculated in Pokémon GO — Full Formula Explained

What Is Combat Power (CP) in Pokémon GO?

Combat Power, or CP, is the single number Niantic displays above every Pokémon to represent its overall strength. It is not a direct battle stat — CP itself is never used inside the damage formula during combat. Instead, it is a summary metric that compresses three hidden values (Attack, Defense, and Stamina) into one easy-to-read integer.

When you catch a wild Pikachu at 456 CP and another at 612 CP, the higher number tells you the second Pikachu has better stats, higher IVs, a higher level, or all three. But CP can be misleading. A Blissey with 2,800 CP is far tankier in battle than a Gengar with 3,000 CP, because the cp formula pokemon go weights Attack far more heavily than Defense or Stamina. Understanding how that weighting works is the first step to building teams that actually win — not just teams that look strong on paper.

CP ranges from a minimum of 10 (every Pokémon has at least 10 CP) up to roughly 5,600+ for a Level 50 Mega Rayquaza with perfect IVs. The cap varies by species because base stats differ dramatically across the Pokédex.

The Official Pokémon GO CP Formula

Niantic has never publicly published the CP formula, but data miners extracted it from the Game Master file within weeks of the game’s 2016 launch. The formula has remained unchanged ever since — even after the Level 50 expansion in 2020 and the Trainer Level 80 update in 2025.

Breaking this down: the formula takes your Pokémon’s base Attack plus its Attack IV (0–15), multiplies that by the square roots of (Base Defense + Defense IV) and (Base Stamina + Stamina IV), then scales everything by the square of the CP Multiplier (CPM) for the Pokémon’s current level. Finally, it divides by 10 and rounds down to the nearest whole number.

Why Attack Is King

Notice that Attack is not square-rooted — it enters the formula at full linear value. Defense and Stamina are both square-rooted, which means they contribute far less to the final CP number. This is why glass cannons like Gengar and Alakazam have deceptively high CP despite being fragile, while tanks like Blissey and Lugia have lower CP than their actual battle durability would suggest. When evaluating a Pokémon for PvP, never rely on CP alone — use the Stat Calculator to see the underlying Attack, Defense, and HP values.

CP Multiplier (CPM) — The Hidden Scaling Factor

The CP Multiplier (CPM) is a level-dependent constant that determines how much your Pokémon’s stats — and therefore its CP — grow with each power-up. Every half-level from 1 to 50 has a unique CPM value hardcoded in the Game Master file. The CPM rises in a curve, not a straight line, meaning early levels see dramatic CP gains while late levels deliver smaller incremental bumps for the same Stardust cost.

Key CPM Values by Level

The CPM at Level 50 (0.8403) is only about 6.3% higher than the Level 40 CPM (0.7903). That small difference is why the jump from 40 to 50 yields roughly 8–10% more CP — not the massive leap many new players expect. The real value of Level 50 is hitting breakpoints in the damage formula, where a slightly higher Attack stat flips a 3-hit KO into a 2-hit KO.

For half-levels, the CPM is calculated as the average of the two adjacent whole-level CPMs. For example, Level 40.5 uses (0.7903 + 0.7953) / 2 = 0.7928. This is why every power-up raises CP by a predictable, smooth amount rather than jumping in chunks.

Base Stats, IVs & How They Feed Into CP

Every Pokémon species has three base stats — Attack, Defense, and Stamina — derived from the main-series Generation 6 stats. These are identical for every member of that species. On top of those base stats, each individual Pokémon adds Individual Values (IVs) ranging from 0 to 15 for each stat. IVs are permanent and never change.

Base Stats Example: Blissey vs. Gengar

Blissey has the highest base Stamina in the game (496) but mediocre Attack (129). Because Attack is not square-rooted in the CP formula, Blissey’s massive HP pool is heavily discounted — giving it a lower max CP than Gengar despite being far superior in gym defense and PvP bulk. This is the single most important reason why combat power calculation should never be your only metric.

IV Impact on CP

A perfect 15/15/15 IV Pokémon will always have higher CP than a 0/0/0 IV Pokémon of the same species and level — but the gap is smaller than most players assume. For a Level 40 Mewtwo, the difference between 0% and 100% IVs is roughly 360 CP. For a Level 40 Blissey, the gap is only about 230 CP. The reason? Mewtwo’s sky-high base Attack (300) amplifies the +15 Attack IV more than Blissey’s low base Attack (129) does.

CP vs. Actual Battle Performance

This is where most trainers get tripped up. CP is not used in the damage formula. When your Pokémon attacks a raid boss or a gym defender, the game calculates damage using raw Attack and Defense stats — completely ignoring the CP number displayed on the summary screen. CP is purely a visual convenience.

How Damage Is Actually Calculated

In this formula, Attack is your Pokémon’s (Base Attack + Attack IV) × CPM. Defense is the defender’s (Base Defense + Defense IV) × CPM. CP never appears. This means two Pokémon with identical CP can deal wildly different damage depending on their stat distributions. A 2,500 CP Medicham (high Defense/Stamina, low Attack) will survive far longer in Great League than a 2,500 CP Haunter (high Attack, terrible bulk) — even though both show the same CP.

When CP Misleads

The 9% Nerf & Special CP Cases

In 2017, Niantic introduced a hidden 9% stat nerf for any Pokémon whose max CP at Level 40 would exceed 4,000. This was implemented right before Mewtwo’s first EX Raid release to prevent a single species from completely dominating every gym and raid. The nerf applies to base stats, not IVs or CPM.

Nerfed Pokémon (9% Stat Reduction)

To calculate CP for a nerfed Pokémon, first multiply its base Attack, Defense, and Stamina by 0.91, then plug the reduced values into the standard CP formula. The 9% reduction is applied before IVs and CPM are factored in. This is why nerfed Pokémon often perform better in PvP than their CP suggests — the nerf reduced their inflated Attack (which hurts CP more than bulk) while preserving relatively more of their defensive stats.

Best Buddy CP Boost

A Best Buddy Pokémon receives a hidden +1 level boost in most contexts — effectively raising its CPM to the next half-level above its actual level. A Level 40 Best Buddy Mewtwo uses the Level 40.5 CPM (0.7928 instead of 0.7903), adding roughly 15–25 CP depending on species. This boost does not allow power-ups past Level 50, but it does let a Level 50 Best Buddy function as if it were Level 50.5 for stat calculations.

How to Calculate CP Yourself: A Step-by-Step Example

Let us walk through a real example: calculating the CP of a Level 40 Mewtwo with 15/15/15 IVs. You can follow these exact steps for any Pokémon using the CP Calculator to verify your math.

CP Caps by League, Format & Encounter Type

Different game modes enforce different CP ceilings. Understanding these caps helps you target the right IV spreads and power-up levels for each format.

Encounter Level Caps & CP Ranges

Wild Pokémon, raid bosses, and eggs all spawn at fixed level ranges, which directly limits their CP:

A weather-boosted wild Tyranitar can spawn at Level 35 with 4/4/4 minimum IVs, giving it significantly higher CP than a raid-caught Tyranitar locked at Level 20 with 10/10/10 IVs — even though the raid version has better IVs. This is why serious PvP players often hunt weather-boosted wild spawns for Great and Ultra League: the higher level allows a lower-IV Pokémon to reach the CP cap with more stat points invested in bulk.

CP Formula FAQ