When you're catching a Pokémon, there is a coloured circle inside the white circle. This circle goes from green to yellow to red. I'm guessing this colour represents the difficulty of capturing that Pokémon because yellow-red Pokémon seem to break free a lot.
However that circle varies in size and goes from being overlaid over the white circle all the way down to tiny little circle I can barely see.
Here the green circle is at max size.
What does this size actually mean? Is it distance that your Pokéball was from the Pokémon or something else?
44 Answers
The ring and its colours are detailed in the official FAQ for Finding and Catching wild Pokémon.
The colour of the ring represents the catching difficulty of the pokémon.
A green ring indicates the capture is low difficulty, orange indicates intermediate difficulty, and red indicates extreme difficulty.
The size of the ring represents your increased chance of catching the pokémon.
6You have the greatest chance of capturing the Pokémon while the colored ring is at its smallest diameter. At the opportune moment, fling the Poké Ball toward the Pokémon.
The smaller the ring, the better chance of catching the Pokémon.
Larger ring = nice throw (10xp)
Medium ring = great throw (50xp)
Smallest ring = excellent throw (100xp)
Curve ball = 10xp
3-A target ring will appear around the Pokémon. The ring’s color indicates the difficulty level of capturing the Pokémon. A green ring indicates the capture is low difficulty, orange indicates intermediate difficulty, and red indicates extreme difficulty.
-You have the greatest chance of capturing the Pokémon while the colored ring is at its smallest diameter. At the opportune moment, fling the Poké Ball toward the Pokémon. Source
- In regards to the bonus; you receive a bonus if you throw the ball inside the ring.
The color of the ring is the difficulty of the catch...Green being easiest followed by Orange then Red being the Hardest. Hitting inside the colored ring as it shrinks will give you bonus Exp as well as a higher chance of catching the pokemon on that cast. Hope this helped :)
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