For a comfortable bedroom, your nightstand should sit between 55 and 70...

https://iris-wiki.win/index.php/Do_American_Nightstands_Run_Taller_Than_UK_Ones%3F_A_Bedside_Guide

For a comfortable bedroom, your nightstand should sit between 55 and 70 centimetres tall. The golden rule is to keep the table surface roughly 5 to 10 centimetres below your mattress-top