IV vs EV: What Is the Difference?

What Are IVs?

Individual Values (IVs) are like a Pokemon's genes. Each of the six stats (HP, Attack, Defense, Special Attack, Special Defense, Speed) gets a hidden number from 0 to 31 the moment the Pokemon is generated, whether it is caught, hatched, or received as a gift. A 31 IV adds 31 points to that stat at level 100 compared to a 0 IV, so the gap is significant.

You cannot train IVs up. In modern games, though, you can use Hyper Training with Bottle Caps to set a stat's effective IV to 31. Important detail: Hyper Training changes the stat calculation, not the underlying gene, so a Hyper Trained parent still passes down its original IVs when breeding.

What Are EVs?

Effort Values (EVs) are training points you earn by battling specific Pokemon or by using vitamins and feathers. The rules are strict: a Pokemon can hold 510 EVs in total, with a maximum of 252 in any single stat. At level 100, every 4 EVs equal 1 extra stat point, which is why the classic competitive spread is 252 / 252 / 4 across three stats.

Unlike IVs, EVs are fully adjustable. Certain berries reduce EVs in a specific stat, so you can retrain a Pokemon for a new role whenever your team plan changes. Our EV training guide walks through the fastest methods game by game.

IV vs EV at a Glance

How They Fit into the Stat Formula

Both values feed into the same stat calculation. Base stats set the foundation, IVs and EVs add on top, level scales everything, and your nature applies a final 10 percent boost to one stat and a 10 percent cut to another (see natures explained). That means a perfect Pokemon is really four decisions stacked together: species, IVs, EV spread, and nature. You can test how different spreads change real damage rolls in our damage calculator.

When a 0 IV Is Actually Better

Perfect 31s are not always the goal. Two common cases where competitive players deliberately want a 0 IV:

0 Speed for Trick Room. Under Trick Room, slower Pokemon move first, so a Trick Room attacker wants the lowest possible Speed: 0 IV, 0 EVs, and a Speed-lowering nature. This is standard practice in VGC formats.

0 Attack against Foul Play and confusion. Foul Play uses your own Attack stat against you, and confusion self-hits also scale with your Attack. A special attacker or defensive pivot that never uses physical moves should run 0 Attack IVs to shrink that damage.

Note that some formats and mechanics read IVs in other ways too, so always check the rules of the event you are entering.

Competitive Readiness Checklist

Before a Pokemon is battle ready, run through this list:

1. IVs are 31 in every stat that matters (Hyper Train if needed), and deliberately 0 where it helps.

2. All 510 EVs are spent, usually 252 / 252 / 4, or a custom spread built around specific matchups.

3. Nature complements the EV spread instead of fighting it.

4. The set covers the threats your team struggles with. Check your weaknesses with the type coverage tool and the type chart.

For example, a physical sweeper like Garchomp typically wants 31 IVs everywhere, 252 Attack and 252 Speed EVs, and a nature that boosts one of those two stats.

Put It into Practice

IVs and EVs only matter in the context of a full team. Open the team builder to plan your six slots, then fine tune spreads once you know each Pokemon's role. If you are starting from scratch, read how to build a Pokemon team first, then come back and optimize. When your sets are final, the Showdown import and export guide shows how to move them into simulators for practice.