What determines my chances of escape from a wild pokemon?
What determines my chances of escape from a wild pokemon?
I've noticed that if Jigglypuff is at the head of my party, I "can't escape" very often. So what about my pokemon makes them more likely to escape?
According to Bulbapedia, the formula is, as of Generation IV:
F = (((A * 128)/B) + 30 * C) mod 256
Where
- F - the probability of escape, out of 256
- A - the attempting Pokemon's speed, before any in-battle modifiers
- B - the opposing Pokemon's speed, before any in-battle modifiers
- C - the number of times escape has been attempted, including this time
-
modmeans "the remainder when divided by"
This means that speed difference between you and your opponent is the key factor (and this is correlated with level), though multiple attempts will also increase your chances.
Interestingly, the mod part means this function loops around - so this implies if you're too fast, or unlucky enough to keep going after enough tries, your probability suddenly drops. Consider the following ratio of your speed to your opponent's, assuming this is your first attempt:
Speed Ratio | Probability of Escape
-----------------------------------
0.01 | 12.2%
0.50 | 36.7%
1.00 | 61.7%
1.50 | 86.7%
1.75 | 99.2%
1.80 | 01.7%
2.00 | 11.7%
I'm unsure if this formula holds in Generations V (Black/White) and VI (X/Y), or battles where there are two opponents (this can happen in Generation IV in certain areas, and in rare normal encounters in subsequent generations). Serebii is happy to place the formula (without the modulo fun) next to screenshots from X/Y, but I'm not going to claim that as confirmation it's remained the same for single battles.