How many couplets does a sonnet have?

There are 14 lines In a Shakespearean sonnet

There are fourteen lines in a Shakespearean sonnet. The first twelve lines are divided into three quatrains with four lines each. In the three quatrains the poet establishes a theme or problem and then resolves it in the final two lines, called the couplet. The rhyme scheme of the quatrains is abab cdcd efef.