In most of the world, including most of the United States, parts of the United Kingdom (England, Northern Ireland, Wales), India and China, the legal adult age is 18 (historically 21) for most purposes, with some notable exceptions:

• The United Kingdom: Scotland (16)
• British Columbia, New Brunswick, Newfoundland and Labrador, Northwest Territories, Nova Scotia, Nunavut, Yukon Territory in Canada; Nebraska and Alabama in The United States, and South Korea (19)
• Indonesia and Japan (20)