For the most comfortable reach, aim for a nightstand that sits 5-10 cm below...
https://www.pop-bookmarks.win/getting-your-bedside-table-height-right-is-key-for-comfort-aim-for-your
For the most comfortable reach, aim for a nightstand that sits 5-10 cm below the top of your mattress. Most standard beds work best with a table height between 55 and 70 cm. Measure your bed while the bedding is on, as that extra thickness matters