Americans’ ideal family size is an average of 2.7 children, Gallup recently discovered, though the US fertility rate — 1.6 children per woman — is the lowest it has ever been in nearly 90 years.

Gallup found that the average ideal number of children has remained fairly consistent in recent decades but noted that the fertility rate continued to fall across the same time frame.

“This suggests that the decline in births may be driven more by practical challenges that make it harder for people to have as many children as they want, rather than by changing attitudes about the ideal family size,” Gallup reported.

The average preferred family size peaked in 1936 and again in 1957, when an average of 3.6 children was considered ideal. In 1973, the ideal number of children dropped to 2.8 and has remained below an average of 3 children ever since. Gallup hypothesized that the shift likely coincided with the publication of the bestselling book The Population Bomb in 1968, which raised concerns about overpopulation across the world, which have since been proven to be unfounded.

The current ideal, 2.7 children, has been consistent since 2018. Gallup found that 40% of Americans say two children is preferred, while 27% consider three children to be ideal. Eleven percent say four children is optimal, and just 4% think having five or more children is best. Two percent said no children is ideal, and four percent said the same of having one child.

Gallup combined the responses into two categories — those who say one or two children is best and those who prefer three or more children — and found that the two opinions are very close to one another after years of polarization. Americans generally have had much stronger preferences for one or two children than three or more, but in 2025, 44% said one or two is best and 42% said the same of three or more children.

Gallup also found that men, weekly or monthly attendees of religious services, Republicans, people of color, and men under age 50 are the most likely to think three or more children is the ideal family size. Those who never or rarely attend religious services, Democrats, white people, adults under age 30, and women under age 50 are most likely to prefer one or two children.