As the other educator pointed out, church records indicate that Shakespeare was baptized at Holy Trinity Church in the town of Stratford-upon-Avon on April 26, 1564.
Many experts believe that the record of Shakespeare's baptism was a transcription. In 1598, the well-worn church registers at Holy Trinity Church were replaced with newer registers. Accordingly, entries for births, baptisms, and deaths from 1558 onward were transferred into these new registers.
So, some speculate that important information could have been lost or recorded improperly. Despite that speculation, historians generally believe that the record of Shakespeare's baptism is genuine. They cite the fact that all new entries were signed and verified by the vicars and wardens of Holy Trinity Church.
Historians use Shakespeare's purported baptism date to calculate his birth date as April 23rd, 1564. Although the Book of Common Prayer (1559) advised parents to baptize their infants on Sunday or the next holy day following the birth, few did so. Shakespeare himself was baptized on a Wednesday.