Population under 18 in St. Johns County
Population under 18 in St. Johns County was 21.6% in 2025, according to the U.S. Census Bureau. That is down 0.4 pts from 2024. That is the 9th highest of 67 counties in 2025.
Population under 18 in St. Johns County, 2010 to 2025
All 16 values
| Period | % |
|---|---|
| 2025 | 21.6 |
| 2024 | 22 |
| 2023 | 22.3 |
| 2022 | 22.5 |
| 2021 | 22.6 |
| 2020 | 22.9 |
| 2019 | 23 |
| 2018 | 23.1 |
| 2017 | 23 |
| 2016 | 23 |
| 2015 | 22.9 |
| 2014 | 22.8 |
| 2013 | 22.8 |
| 2012 | 22.8 |
| 2011 | 23 |
| 2010 | 23 |
Compared with Florida and United States
| Place | 2025 |
|---|---|
| St. Johns County | 21.6 |
| Florida | 18.9 |
| United States | 21.1 |
Rankings
Definition
Residents aged 0 to 17 as a percentage of total population on 1 July. United States: Census Bureau county population estimates by age; states and the nation are sums of their counties.
Uses the US age of majority. Not comparable with population_0_14_share, which stops at 14.
How to cite
U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
Citation styles
APA 7
U.S. Census Bureau. (2026). Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties (Population under 18, St. Johns County, 2010 to 2025) [Data set]. Retrieved October 12, 2026, from https://www.census.gov/programs-surveys/popest/data/data-sets.html
MLA 9
Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Population under 18, St. Johns County, 2010 to 2025. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/en/population-under-18/st-johns-county-florida. Accessed 12 Oct. 2026.
Chicago (author-date)
U.S. Census Bureau. 2026. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Population under 18, St. Johns County, 2010 to 2025. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/en/population-under-18/st-johns-county-florida.
Harvard
U.S. Census Bureau (2026) Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Population under 18, St. Johns County, 2010 to 2025 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/en/population-under-18/st-johns-county-florida (Accessed: 12 October 2026).
BibTeX
@misc{census_population_under_18_st_2025,
author = {{U.S. Census Bureau}},
title = {{Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Population under 18, St. Johns County, 2010 to 2025}},
year = {2026},
howpublished = {Data set},
url = {https://www.census.gov/programs-surveys/popest/data/data-sets.html},
urldate = {2026-10-12},
note = {Accessed via Invokely, https://invokely.ai/en/population-under-18/st-johns-county-florida. Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.},
}
RIS
TY - DATA
AU - U.S. Census Bureau
TI - Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Population under 18, St. Johns County, 2010 to 2025
PY - 2026
DA - 2026/06/25
PB - U.S. Census Bureau
DB - Invokely
UR - https://www.census.gov/programs-surveys/popest/data/data-sets.html
L2 - https://invokely.ai/en/population-under-18/st-johns-county-florida
Y2 - 2026/10/12
N1 - Accessed via Invokely, https://invokely.ai/en/population-under-18/st-johns-county-florida.
N1 - Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
ER -
Use this data in your AI agent
Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:
What is the latest population under 18 in St. Johns County? Cite the source.
get_value {"indicator":"population_0_17_share","place":"us-county-12109"}
GET https://invokely.ai/api/v1/value?indicator=population_0_17_share&place=us-county-12109
Questions
What is the population under 18 in St. Johns County?
Population under 18 in St. Johns County was 21.6% in 2025, according to the U.S. Census Bureau. That is down 0.4 pts from 2024. That is the 9th highest of 67 counties in 2025.
Where does this figure come from?
U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 0 to 17 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Retrieved by Invokely on 2026-10-12.
What was the highest population under 18 in St. Johns County?
23.1% in 2018, the highest value since 2010 in this series.
Related statistics for St. Johns County
- Live births, July to June
- Residents who moved from another state in the past year
- Median age on 1 July (US county estimates)
- White (non-Hispanic) population share
- Depression in adults, local model estimate
- Fair Market Rent, two bedrooms (HUD, monthly)
- Traffic fatalities
- Adult obesity rate, local model estimate
All statistics for St. Johns County | St. Johns County in figures