How many milgrams in 1 tablespoon?

How many milligrams of what? Milligrams measure weight and tablespoon measures volume. If you had a tablespoon of salt, that would be 15083 milligrams, BUT a tablespoon of say, something bigger like cranberries, it would be 6210 milligrams. I always use this free site to help me with all sorts of conversions. From grams to ounces to celsius to meters to all kinds of things. http://www.onlineconversion.com