Explaining Catch Rates

You’ll probably want to refer to guides to see what the catch rate for individual Pokemon are. (Serebii lists the Pokemon catch rates.) CatchRate is specific to each Pokemon. Higher is easier to catch. Abra is a 200, which means it is more difficult to catch than Geodude, which is 255.

There’s a math formula for figuring out how easy it is to catch a Pokemon:

( ( 3*MaxHP - 2*CurrentHP) * CatchRate) / 3*MaxHP

When you throw a PokeBall, it’ll quickly figure out your chances, against a random number that is generated between 0 to 255.

Let’s try to catch that Abra. It uses Teleport as its only attack, so we'll only get one shot at it. The level 8 Abra has 24 HP. I’ll try to throw a regular Pokeball, while Abra is unhurt. It’s MaxHP and Current HP are the same – it works out to 3(24) – 2(24) = 1(24) = 24. Multiply it by 200, Abra’s CatchRate, and you end up with 4800. Divided by three times its MaxHP, it’s got a 67. Against the random number generator, you’ll catch an unhurt 24 HP Abra about 25% of the time, before it teleports away.

Improving capture methods:

The actual formula adds more modifiers, for special conditions and what kind of ball you use:

Status * BallModifier * ( ( 3*MaxHP - 2*CurrentHP) * CatchRate) / 3*MaxHP

Status is the effect of a special condition, the higher the number, the better.

Frozen or Asleep: 2

Paralyzed, Poisoned, or Burned: 1.5

Other conditions/no condition: 1

As you can see, Asleep is the best modifier (Frozen is really good, but hard to use - there aren't a lot of moves that freeze reliably.) If Asleep won't work against the Pokemon, I'll try Paralyzed...it doesn't run the risk of KO'ing the Pokemon, like Poisoned or Burned does.

The higher the BallModifier, the more your chances improve:

(Specialty Balls always have a minimum multiplier of x1.)

Poke Ball, Premier Ball, Luxury Ball, Heal Ball: x1

Great Ball: x1.5

Ultra Ball: x2

Dive Ball: x3.5 for underwater Pokemon (Ruby/Sapphire/Emerald) or Pokemon in water for other games

Nest Ball: x3 for Pokemon levels 1-19, x2 for levels 20-29

Net Ball: x3, but only for Water-type and Bug-type

Repeat Ball: x3, but only for Pokemon you’ve already caught

Dusk Ball: x4, but only works at night or underground

Quick Ball: x4, but decreases every 5 rounds – after round 16 it stays at x1

Timer Ball: x4 at 30 rounds or more, x3 for 20-29 rounds, x2 for 10-19 rounds

Let’s take a second look at catching that Abra. If I manage to get it Asleep before it uses Teleport, I double my chances catching it with a Poke Ball. If I use an Ultra Ball, it doubles my chances again – my 67 * 4 = 268 will always be higher than the random number being generated.

In wrap-up, there are several different formulas out there for figuring out catch rates. Some of them didn’t work mathematically, while others didn’t match my experiences. As nothing official has ever been posted about it, I’d use these as ideas on how to improve your catching experiences.