IVs Explained: What They Are and Why Your “Bad” Pikachu Might Still Be Great

If you’ve spent any time in Pokémon GO communities, you’ve seen someone dismiss a Pokémon as “trash” because it’s “only 82% IV.” That framing isn’t wrong, exactly, but it’s incomplete — and taken too literally, it leads a lot of trainers to transfer Pokémon that would have been perfectly good for what they actually wanted to do with them.

What an IV actually is

Every Pokémon has three Individual Values: Attack, Defense and Stamina, each randomly assigned a whole number between 0 and 15 the moment it’s caught or hatched. These are permanent for that specific Pokémon and layer on top of its species’ fixed base stats. Two Charizard with identical levels can perform differently in battle purely because one rolled better IVs than the other.

“IV percentage,” the number most calculators and appraisal tools report, is just the sum of all three IVs out of a possible 45, expressed as a percentage. A “100% IV” Pokémon has 15/15/15. An “82% IV” Pokémon has a combined total of roughly 37 out of 45 — still a very strong roll, despite how “82%” sounds next to a perfect 100.

Where IV percentage is genuinely useful

For raid attacking and Gym defense, overall IV percentage is a reasonable shorthand, because in those contexts you generally want a Pokémon that’s simply as strong as possible across the board, with no CP cap to work around. A 100% IV raid attacker will out-damage a 40% IV one of the same species and level, full stop.

Where IV percentage actively misleads you

In GO Battle League, every match happens under a CP cap (1500 for Great League, 2500 for Ultra League, no cap for Master League). Once you introduce a cap, total IV percentage stops being the right measurement, because a Pokémon with high Attack IVs hits the CP cap at a lower level than one with high Defense/Stamina IVs — which means the high-Attack Pokémon ends up with less overall bulk once both are capped at the same CP.

This is why serious PvP players look for specific PvP IV rankings for a given league rather than raw overall percentage. A Pokémon appraised as “not the best” for raids can rank in the 99th percentile for Great League specifically, because what makes a great PvP Pokémon (low Attack, high Defense/Stamina, so it reaches a higher level before capping) is close to the opposite of what makes a great raid attacker.

How to check your Pokémon’s IVs

Niantic doesn’t show raw IV numbers in-game. You have two practical options:

• Team Leader Appraisal — free, built into the game, and tells you a rough tier plus which stat is your Pokémon’s best. It won’t give you an exact number.
• Work backward from CP and HP — since CP and HP are both direct functions of a Pokémon’s base stats, IVs and level, knowing all three of CP, HP and level narrows down the possible IV combinations mathematically, often to a single exact answer. Our IV Calculator does exactly this: enter your Pokémon’s species, CP and HP, and it returns the matching IV combination(s).

The bottom line

Don’t transfer a Pokémon just because a calculator shows a modest overall IV percentage. Ask what you actually want it for first. If it’s a PvP piece for a capped league, check its PvP-specific ranking rather than its raw IV total. If it’s a raid attacker, overall percentage is a fine shortcut — but even then, a good moveset usually matters more than the last few percentage points of IV.

A concrete PvP example

Imagine two Azumarill, both caught in the wild. Azumarill A has 15 Attack / 8 Defense / 9 Stamina IVs (overall about 71%). Azumarill B has 4 Attack / 15 Defense / 14 Stamina IVs (overall about 73%, barely different by the usual metric). In Great League, Azumarill B will typically outperform Azumarill A, because its lower Attack IV lets it reach a higher level before hitting the 1500 CP cap — and that extra level translates into more overall bulk (both Defense and Stamina scale with level too). A raw IV percentage comparison would call these two nearly identical. A PvP-specific ranking would correctly identify B as the far better Great League pick, often by a wide margin.

Appraisal, decoded

When your Team Leader appraises a Pokémon, the flavor text maps to specific IV percentage bands: phrases like “overall, your Pokémon is a wonder, what a fantastic Pokémon” indicate a top-tier roll (typically 100%), while more muted phrasing indicates a middling one. The appraisal also tells you which single stat is highest, tied, or lowest relative to the others — useful context, but still not the same as an exact number. Pairing an in-game appraisal with a CP/HP-based calculation is the closest you can get to certainty without Niantic simply displaying the numbers outright.

Do IVs change over time?

No. A Pokémon’s IVs are fixed permanently the moment it’s caught, hatched, or received via trade (trading can occasionally adjust a friend’s Pokémon’s IVs slightly upward as a trade bonus, but this is the one exception, and it happens automatically as part of the trade itself — you can’t influence which stat improves). Powering up, evolving, or using a Technical Machine to change a moveset never alters IVs. If you want a Pokémon with better IVs, your only real options are catching more, hatching more, or getting lucky on a trade.