A high degree of strabismus is immediately apparent. However, smaller deviations are barely observable (micro-strabismus) and appear less serious. This is certainly not the case, as the consequences will be the same; even in cases of micro-strabismus, a lazy eye with poor visual acuity is often the result.

In strabismus which develops after the first 8 years of life the chance of developing a lazy eye is small, but double vision can occur. A sufferer might squeeze one eye shut, hold his or her hand in front of one eye or complain of double vision. Furthermore, people with squint can present with motor symptoms such as stumbling and grabbing for but missing an object placed next to them, as well as find it difficult to estimate distances.