It is not possible to generalize whether 0.8 vision is normal. For young preschoolers, a vision of 0.8 is usually normal, while it is not normal for adults. For preschoolers, 0.8 vision is usually normal because visual function is not yet fully developed and vision development increases with age, and can gradually increase to 1.0 and above with age. However, for adults, 0.8 vision is not normal and is considered mild vision loss. Because normal vision for adults is 1.0 and above, a vision of 0.8 is usually considered to be a possible mild refractive error or the presence of an eye disease. Whether it is a child or an adult, if the visual acuity is 0.8, it is recommended to go to the regular hospital for a clear diagnosis and follow the doctor’s instructions.