Getting ready to install my hardwood floor and the Fireplace hearth is about 1/4 in over 18in out of square with where I plan to run the flooring. If I run the flooring square to the tile hearth it is going to be off about 3/4 over every 10 feet to every wall and island in the rest of the room. I wanted to frame the hearth but the builder put it in before I was ready. How can I frame it with out making it look bad? or am I stuck with a dreaded transition piece.

divide it in half and back fill with some caulk/mortar..

cant really decipher from what you've said..but this seems most logical

Run your entire installation at a 45º angle to the square walls.
Or....
Cheating 1/32 in each row, 32 rows and you have gained an inch

Thanks! I will see what the wife has to say about the 45.

Every angled installation I see, just looks stunning compared to a sq. lay.
That custom look, and it hides all out of square walls. In your case, the hearth.

I did one install that the architect wanted on a 22.5 angle. I thought to myself, this is going to look like I screwed up and got it out of square. It looked awesome when I was done. Very contemporary, artsy-fartsy.

Or undercut it if possible and make sure you have most of a plank next to it. You'll never see a 1/4 inch in 18 in. Never run your floor to something like that