Child marriage is any formal marriage or informal union in which at least one partner is under 18. UNICEF estimates that 640 million girls and women alive today were married as children, and that about 12 million girls became child brides in 2022 alone. The practice is slowly becoming less common: the share of women aged 20 to 24 who were married before 18 fell from 24.2% in 2005 to 22.0% in 2015 and 18.5% in 2025, and the share married before 15 fell from 7.8% to 4.2% over the same twenty years. Boys are also affected, though far less often: in 2019 UNICEF estimated that 115 million boys and men had been married as children.
Child marriage is most common in sub-Saharan Africa, where 31% of young women were married before 18 in 2025, and in South Asia, at 25%. Because of its large population, South Asia is home to about 45% of all girls and women married as children, and India alone to about a third. West and Central Africa has made little progress in 25 years and has 7 of the 10 countries with the highest rates. Marrying as a child can end a girl's education, limit her later earnings, lead to early motherhood and leave her isolated in a relationship in which she has little power to claim her rights. Progress has mostly reached girls from richer families, and conflict and climate shocks are linked to rises in child marriage.
How child marriage is defined and measured
SDG target 5.3 calls for the elimination of harmful practices, including child, early and forced marriage, and UNICEF is the agency responsible for tracking it. The official indicator looks back at the experience of young adult women rather than counting marriages as they happen. Four elements shape the figures:
The age line is 18
A marriage counts as a child marriage if it took place before the person's 18th birthday. The indicator also reports marriages before age 15, the earliest and most harmful form: worldwide, 4.2% of women aged 20 to 24 in 2025 had been married before 15.
Informal unions count too
The definition includes informal unions in which a couple lives together as if married, not only formal marriages. Survey questions therefore ask about the age at which a woman first married or began living with a partner.
Measured among women aged 20 to 24
SDG indicator 5.3.1 is the share of women aged 20 to 24 who were first married or in a union before age 15 and before age 18. Asking women who have recently passed 18 captures the full experience of childhood while still reflecting recent practice.
Survey-based, modelled estimates
Country figures come from household surveys such as DHS and MICS. The 2025 world estimate is modelled from data collected between 2016 and 2025 in 119 countries covering 82% of women aged 20 to 24, with adjustments for countries without data. Estimates for boys come from a separate analysis of 82 countries.