《礼记·内则》
到了十五岁，举行笋礼，表示已进入成年。到了二十岁，可以出嫁；如有特殊原因，可推迟到二十三岁才嫁。
十有五年而笄，二十而嫁；有故，二十三年而嫁。
At the age of fifteen, the Sun Ritual was held to mark the transition to adulthood. At the age of twenty, you can get married; if there are special circumstances, you can postpone getting married until the age of twenty-three.