21.24% of Sidoarjo Regency's population in 2023 was aged 0-14 years.

According to 2023 data from the Central Statistics Agency (BPS), 1.34 million or approximately 67.26% of the population in Sidoarjo Regency are in the productive age group (15-59 years old). Meanwhile, 21.24% of the total population, or approximately 424,070, are children (aged 0-14 years), and another 11.51% are residents over 60 years old.

The population of Sidoarjo Regency was recorded at 2 million people as of December 2023. This figure is higher than in June 2023 and December 2021. Compared to the previous five years, the Compound Annual Growth Rate (CAGR) of this region is lower. The growth over the last five years was recorded at -2.35%.

Compared to other regencies/cities in East Java Province, Sidoarjo Regency's population ranks among the top five. When viewed by island, it ranks 20th.

The following is the population by age group in Sidoarjo Regency in December 2023, sourced from publications by the Central Statistics Agency (BPS):

* Age 0-4 years: 119,680 people (5.99%)
* Age 5-9 years: 146,240 people (7.32%)
* Age 10-14 years: 158,150 people (7.92%)
* Age 15-19 years: 144,000 people (7.21%)
* Age 20-24 years: 162,770 people (8.15%)
* Age 25-29 years: 154,590 people (7.74%)
* Age 30-34 years: 144,470 people (7.23%)
* Age 35-39 years: 144,950 people (7.26%)
* Age 40-44 years: 162,550 people (8.14%)
* Age 45-49 years: 150,940 people (7.56%)
* Age 50-54 years: 153,770 people (7.70%)
* Age 55-59 years: 124,920 people (6.26%)
* Age 60-64 years: 95,360 people (4.78%)
* Age 65-69 years: 64,280 people (3.22%)
* Age 70-74 years: 35,020 people (1.75%)
* Age 75 years and over: 35,120 people (1.76%)