What is the amount of sperm in single ejacuation?

A lot: The average man has between 20-150 million sperm per cc of ejaculate with motility of 40+% and a volume of 2-5cc. Multiply the numbers per cc times the volume and you will get an average amount of sperm per ejaculation. Hope this helps.

Only need one . . .: You only need one sperm to make a baby. And some sperm do sneak out even before you ejaculate which is why withdrawal method doesn't work really well. With that said, number of sperm per ejaculation depends upon who you ask. Some say 300 million while others report 300 million/ml w/avg ejaculate ranging 1-5ml or even as high as 5-10ml depending upon source. Have fun searching online for an answer!

40to 600 million: In one ejaculation there may be 40to600million sperms, average amount of ejaculation fluid is half a spoonful.And it is combination of sperms and fluids from prostate and urinary tract sperm production decreases with age and ends at death.