How much iron do i need every day?

It depends: This question is very complex and depends on a lot of factors. If you are healthy and not anemic, and eat a well balanced diet, you will likely get the iron you need from your diet and not require any supplemental iron. For an excellent reference that breaks down iron requirements see the nih's web page on iron information and daily intake requirements at http://ods.Od.Nih.Gov/factsheets/iron/#h.

Iron: 15-25mg for men, 18-30mg for women. Best.

Iron requirements: Vary according to age, gender, menstruating, pregnancy, lactating. See chart from the office of dietary supplements of the nih given here.