For the most comfortable setup, aim for your bedside table to sit roughly 5-10...

https://www.third-bookmarks.win/for-a-comfortable-bedroom-aim-for-a-bedside-table-that-sits-5-10-cm-below-your

For the most comfortable setup, aim for your bedside table to sit roughly 5-10 cm below the top of your mattress. This makes it effortless to grab your phone or a glass of water without straining your arm