Pokemon Catch Rate Calculator (Gen 3)
Calculates capture probability for Ruby, Sapphire, Emerald, FireRed, and LeafGreen.
Legendaries: 3, Snorlax: 25, Starters: 45.
Poke Ball (1x)
Great Ball (1.5x)
Ultra Ball (2x)
Net Ball (Bug/Water) (3x)
Dive Ball (Underwater) (3.5x)
Repeat Ball (If Caught) (3x)
Premier/Luxury Ball (1x)
Master Ball (Auto-catch)
None (1x)
Sleep / Freeze (2x)
Paralysis / Poison / Burn (1.5x)
Results:
How Gen 3 Catch Rate Logic Works
In Generation 3 (Hoenn and Kanto remakes), the catch rate is determined by a specific mathematical formula that factors in the Pokemon's health, its status condition, and the type of Poke Ball used. Unlike later generations, Gen 3 mechanics are strictly defined by an integer calculation.
The Formula:
a = (((3 * MaxHP – 2 * CurrHP) * CatchRate * BallModifier) / (3 * MaxHP)) * StatusModifier
If a is 255 or greater, the Pokemon is caught automatically. If not, the game generates a series of random numbers to determine if the ball shakes or breaks.
Key Variables Explained
- Base Catch Rate: Every Pokemon species has a hidden value. For example, Rayquaza and Beldum have a rate of 3, making them incredibly difficult to catch, while Caterpie has 255.
- HP Factor: Reducing a Pokemon to 1 HP significantly increases the value of a. The formula rewards you for getting the current HP as low as possible.
- Status Modifiers: Putting a Pokemon to Sleep or Freezing it provides a 2x bonus, which is superior to Paralysis, Poison, or Burn (1.5x).
Example Calculation
Imagine you are trying to catch a Kyogre (Base Catch Rate: 3) in Pokemon Emerald:
- Kyogre is at 10/100 HP.
- You use an Ultra Ball (2x modifier).
- Kyogre is Asleep (2x status modifier).
Plugging this in: (((300 - 20) * 3 * 2) / 300) * 2 = 11.2. Since 11.2 is much lower than 255, your catch chance per ball is roughly 4.39%.