Calculator
Stronghold Finder
An Eye of Ender points at the stronghold but never tells you how far. Two throws from different positions give two lines, and where they cross is the portal room. Enter the F3 position and facing angle from each throw and this works out the intersection, so you stop walking the moment you are on top of it.
Calculator
Stronghold Finder
Throw an Eye of Ender, press F3, and copy your position and the Facing angle while looking straight at the eye. Walk a few hundred blocks sideways and repeat.
Throw 1
Throw 2
Stronghold X-43
Stronghold Z-43
Distance from throw 2~247 blocks
Accuracy depends entirely on how precisely you face the eye. Take the second throw at a wide angle to the first; two throws only a few degrees apart will land you hundreds of blocks off.