When trying to capture a Pokemon in Pokemon Go, players will notice that the ring around the creature is a slightly different color every time. This is actually an extremely useful piece of information if you know what the colors indicate.
Simply put, the colors are there to let you know how difficult of a capture this Pokemon is. Green indicates that it is relatively easy to capture, while red indicates that it is rather difficult.
To get even more specific, a Reddit user recently found that there are roughly 511 possible colors. When breaking this down into color codes, that’s everything from 0xFF0000 (red) to 0x00FF00 (green).
This red represents a 0 percent chance, although no Pokemon actually has a zero percent chance of capture. This orange indicates a 25 percent chance. This yellow represents a 50 percent chance. This yellow/green represents a 75 percent chance. And this green represents a 100 percent chance. Using this information, you can figure out where the color of the ring falls on this spectrum and get a rough percentage of what your chances are.
This research also found that using a Razz Berry has absolutely no affect on the ring color. This item is said to make it easier to capture Pokemon, and while that’s true, it only means that Pokemon will be less likely to escape once you’ve already hit them; it doesn’t make the actual throw any easier.
One element that does appear to affect the ring color, though, is what type of ball you use; whether you use a regular Poke Ball, a Great Ball or an Ultra Ball appears to alter the ring color, with better Poke Balls making it easier to capture high CP Pokemon.