The golden rule for bedside tables is comfort and accessibility. Aim for a...

https://www.oscarbookmarks.win/aim-for-your-bedside-table-to-sit-5-to-10-cm-below-the-top-of-your-mattress

The golden rule for bedside tables is comfort and accessibility. Aim for a height that sits between 5 and 10 centimetres below the top of your mattress. Most standard beds work best with a table height between 55 and 70 centimetres