I have created versions of some world maps that have superimposed grids. These grids indicate the game coordinates as they are found in editors such as the Creation Kit and xEdit. These grids should make it easier to locate items of which you only know the coordinates.
Details on how the maps were created and how the grids were calculated can be found on the respective images' pages.
Fallout 4[]
In this map, each major gridline corresponds to 50,000 coordinate points while each minor gridline corresponds to 25,000 coordinate points. Note that the map markers do not exactly correspond to those found in-game, but the original grid (in green) underneath does.
Fallout 76[]
In this map, each major gridline corresponds to 100,000 coordinate points while each minor gridline corresponds to 12,500 coordinate points. This map corresponds exactly to the one found in-game since the map was extracted from the game files.
Note that there also exists an interactive map with all locations of all items. (Kudos to Canyon Light for pointing this out.)
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