There is essentially no difference between an astigmatic axial position of 180° and 10°. It is mainly related to the amount of astigmatism and the purpose of the optometry. In general, the smaller the astigmatism, the greater the axial tolerance, which must be accurate if children need glasses, or for pre-operative keratoconus examinations. An astigmatic axial tolerance of 180° means that a patient with astigmatism, sees better at 180°, whereas an astigmatic axial tolerance of 10° means that he/she sees better at 10°. Low astigmatism and axial errors within a certain range do not affect vision very significantly, while higher astigmatism or a slight axial error can affect vision. The difference between 180° of astigmatism and 10° is only about 10°. As long as the astigmatism is within 75°, it will not affect the quality of vision. If it exceeds 75° or more, a prismatic effect may occur, with eye fatigue, etc. If special circumstances arise, precise astigmatic axial position may be required. Children’s astigmatism requires accuracy, giving accurate astigmatism and axial degrees, wearing corrective lenses, obtaining better retinal visual quality, and thus promoting visual development and avoiding the formation of amblyopia.