The standard build used for this estimate
This page uses a practical standard build: white rice, black beans, chicken, fajita vegetables, fresh tomato salsa, roasted chili-corn salsa, cheese, and romaine lettuce. If your bowl uses brown rice, pinto beans, sour cream, guacamole, queso, or double chicken, the macros will change.
Chipotle is highly customizable, so one 'chicken bowl' can be 500 calories or more than 1,100 calories. That is why the build matters more than the menu name.