http://www.cycletourist.com/biochart/.
You need to put in your birthdate, then the month you conceived, and then the time zone. If you need to figure out conception date, try this webiste to backtrack from birthdate.
http://dateoflife.com/prod02.htm
The blue line is the physical line, red is emotional, and green is intellectual. Ignore the green line.
If the blue line is in the positive zone and red line is in the negative zone, then you have a strong chance of conceiving a boy.If the both blue and red are in the positive zone, then you lean towards having a boy.
If the red line is in the positive zone and blue line is in the negative zone, then you have a strong chance of conceiving a girl.
If the both the red and blue are in the negative zone, then you lean towards having a girl.
It also shows moon phases. Full moon = boy; New moon = girl