This is a very incomplete list of ages at which people are allowed to marry in various countries.
Australia: 18 generally, 16 under special circumstances with court approval.
Brazil: 18 generally; 16 with parental consent; unlimited in case of pregnancy; 12 with judicial consent (only to avoid partner from going to prison as a sex offender)
Canada: 18 generally, 16 with parental consent, 14 with judicial consent.
United States: Usually 18. Most states, however, allow marriage at a younger age with parental or judicial consent. Some states allow marriage at a still younger age if the female is pregnant or with child.
California: 18 generally, unlimited with parental consent.