RealAge does not pretend to be an accurate tool and exists as a free entertainment project.
This project does not guess your age, but gives an assessment of how you look under certain conditions (the position of the face in the frame, lighting).
To get a more accurate result, it is necessary to provide the most acceptable conditions such as the size and direction of the light, the position of the face in the frame , and so on.
RealAge is based on its own ML models implemented using the Apple Create ML tool.