What is the best tie knot?

I dont know about "the best", but the four-in-hand is pretty popular on this forum. I personally always go for the FIH when I'm wearing a tie.

Whichever one you can tie well. For me, it is the half-Windsor, with a nice dimple. However, I can rock the FIH or the Windsor too. Or a bowtie (my favorite).

Half-windsor all the way! Much more symmetrical than the four-in-hand, though you have to make sure to tie it fairly well with a thick silk tie (particularly a seven-fold), or else you end up with a globby mess. Windsor's even worse for that.

The answer depends on factors such as the width of the tie, type and quality of fabric from which the tie is made, and the width of the collar gap the knot will fill.

Id like to turn the trajectory of this thread towards balloon knots.

pics pls

Best knot is "The Mt_Spiffy"

 

4 in hand.

FIH>>>>>>

"Best" knot depends upon the tie and shirt collar style. I use a Pratt knot for most of my silk ties and a FIH for knit ties.

FIH.  The Gentleman's Academy says so:

 

http://www.youtube.com/watch?v=_uZy6exIDKo

Fat Knot.

 

http://www.youtube.com/watch?v=X6LwT0o-LTk