This is an incomplete list of the average ages of people when they first marry in various countries. This list is current (from year 2000 or later) and does not treat the topic in history.
Because the age distribution of the marriageable population is skewed, the median age is a more precise representation of the average age. However, for most reporting sources, only the mean ages are given. A still more accurate and precise method of representation, one not distorted by either omitting unmarried people from the sample or falsely treating their current age as their age of first marriage, is to take a sample of persons at each of a set of evenly spaced age increments, beginning with the age of legal eligibility of marriage and ending at the highest age for which a sufficiently large sample of living persons can be found, asking each member of each sample whether s/he has ever been married, and defining the average age of first marriage as the lowest age interval among whose members 50% or more answer "yes."