You can test your child’s vision at home if you notice some symptoms of vision problems. However, remember this test cannot replace the comprehensive eye exam by an ophthalmologist. A comprehensive eye exam is more accurate and can detect underlying health problems. A home test can help determine if your child needs to see an eye doctor for further assessment. If your child is below three years old, they should be able to see the 20/40 line of the chart. Children aged 3-4 should see the 20/30 line, while those aged five years and older should be able to read well the 20/20 line of the chart.