Due date calculations methods

Je

As my DD approaches, I've been looking at different methods to calculate due date. I only know of four.

LMP (also Naegele's rule)- Aug 17

Date of conception- Aug 19

By Ultrasound- Aug 20

Woods Method- Aug 30 (oh plz no)

My official DD at my OB was by US method (August 20) so I was just looking for other methods for fun :) Thoughts?