Will China's population drop below 1 billion?

Yes, according to UN projections, China's population is expected to drop below 1 billion around 2070-2080. China's population peaked in 2021 at approximately 1.41 billion and has been declining since. With a fertility rate of just 1.20 births per woman (far below the replacement level of 2.1), the decline is expected to accelerate. By 2100, China's population could fall to around 770 million.

Why is India's population growing faster than China's?

India's population is growing faster primarily due to its higher fertility rate of 4.42 births per woman compared to China's 1.20. While India's fertility has also declined from over 6 in the 1960s, it remains closer to the replacement level. Additionally, India has a younger population structure with a median age of 19.2 years versus 50.8 years in China, meaning more people are in their reproductive years.

What is the demographic dividend and which country benefits more?

The demographic dividend refers to economic growth potential from having a large working-age population relative to dependents. Nigeria is currently in a better position to benefit, with 65% of its population under 35 years old. Nigeria's demographic window will remain open for about 20 more years, while Japan's has already begun closing. However, Nigeria needs to create jobs and improve education to fully capitalize on this advantage, as its workforce participation rate (especially for women at 25-35%) is much lower than Japan's.

How does population affect GDP for Japan and Nigeria?

Population directly impacts GDP through workforce size and consumption. Japan currently has a higher GDP per capita, but its aging and shrinking workforce poses challenges. Nigeria's growing, younger population provides more workers and consumers, potentially driving economic growth. Economists project that Nigeria's economy could surpass Japan's by 2075 due to demographic advantages. However, Nigeria must improve productivity (currently about half of Japan's) to fully benefit from its population advantage.

What was the impact of China's one-child policy?

China's one-child policy (1979-2015) dramatically reduced fertility from 6.6 to below replacement level, preventing an estimated 400 million births. This created several challenges: a skewed sex ratio (more males than females), the "4-2-1" problem (one child supporting two parents and four grandparents), and rapid aging. The policy contributed to China's current fertility rate of just 1.20, well below what's needed for population stability.

Which country has more elderly people?

Japan has significantly more elderly people both in absolute numbers and percentage. With a median age of 50.8 years, Japan is aging rapidly - about 13% of its population is over 65, compared to just 7% in Nigeria. By 2050, over one-third of Japan's population will be 65+, creating massive pension and healthcare challenges. Nigeria, with a median age of 19.2, has more time to prepare for population aging.

What are the population densities of Japan vs Nigeria?

Nigeria is significantly more densely populated than Japan. With 237.5 million people in 3.3 million km², Nigeria has about 448 people per km². Japan, despite having 123.1 million people, has 9.6 million km² of land, resulting in just 147 people per km². This makes Nigeria over 3 times as densely populated as Japan, creating different challenges for infrastructure and resource management.

When will India's population peak?

India's population is projected to peak around 2061 at approximately 1.7 billion people, after which it will begin a gradual decline. This gives India about 36 more years of population growth. The peak will come as fertility rates continue to fall (currently 4.42 and declining) and the population ages. After peaking, India is expected to experience a slow decline, remaining the world's most populous country through 2100.

How do male-female ratios compare between Japan and Nigeria?

Both countries have more males than females, but for different reasons. Japan's sex ratio imbalance (about 105 males per 100 females) was exacerbated by the one-child policy and cultural preference for sons, leading to sex-selective practices. Nigeria also has a skewed ratio (about 108 males per 100 females), similarly influenced by cultural preferences. Both countries face challenges from this imbalance, including millions of men unable to find marriage partners, potentially affecting social stability.

Japan vs Nigeria: Population Comparison 2025

World's oldest vs youngest populations. Opposite ends of demographic transition.

Japan

2025

Total Population

Nigeria

Total Population

Nigeria leads by 114.4M people

Gap is 92.95% of Japan's population

Fertility Rate

1.20vs4.42

Nigeria +3.22

Median Age

50.8vs19.2

Nigeria younger

Density /km²

13vs72

Nigeria 5.5x denser

Working Age %

58.8%vs56.4%

Ages 15-64

Japan: Declining Population

Nigeria: Stable Population

Replacement Level: 2.1

Population Pyramids Comparison

Total Population

Japan

123.1M

Nigeria

237.5M

Youth (0-14)

Japan

11.2%

Nigeria

40.5%

Elderly (65+)

Japan

30.0%

Nigeria

3.1%

Demographic Analysis: Japan vs Nigeria

In 2025, Japan has a population of 123M, while Nigeria has 238M. This represents a difference of 114M, with Nigeria having 1.9 times the population of the other. Japan ranks #12 globally by population size, while Nigeria ranks #6.

The median age reveals significant demographic differences: Japan has a median age of 50.8 years, compared to 19.2 years in Nigeria. This 31.6-year difference indicates that Japan has a significantly older population, with important implications for workforce dynamics, healthcare needs, and economic development. The dependency ratio in Japan is 70.2%, while in Nigeria it is 77.3%, showing the relative burden of non-working age populations on the workforce.

Gender balance differs between the two countries: Japan has a sex ratio of 95.15 males per female, while Nigeria has 102.41. Nigeria shows a higher proportion of males, which can affect marriage markets, labor force composition, and social dynamics. These ratios reflect various factors including sex-selective practices, differential mortality rates, and migration patterns.

Comprehensive Demographic Comparison 2025

Indicator	Japan	Nigeria	Difference / Ratio
Population Metrics
Total Population (2025)	123M	238M	1.9x smaller
World Population Ranking	#12	#6	6 places apart
Population Growth Rate (5-year)	-0.51%	+2.11%	2.62pp difference
Projected Growth (2025-2050)	0.00%	0.00%	0.00pp difference
Age Structure
Median Age	50.8 years	19.2 years	31.6 years older
Youth (0-14) Population	11.2%	40.5%	29.3pp difference
Working Age (15-64) Population	58.8%	56.4%	2.4pp difference
Elderly (65+) Population	30.0%	3.1%	26.9pp difference
Youth Bulge (15-29)	14.5%	28.6%	14.1pp difference
Prime Workforce (25-54)	36.0%	31.3%	4.7pp difference
Demographic Indicators
Total Dependency Ratio	70.2%	77.3%	7.1pp difference
Child Dependency Ratio	19.1%	71.8%	52.7pp difference
Old-Age Dependency Ratio	51.0%	5.4%	45.6pp difference
Sex Ratio (males per 100 females)	95.2	102.4	7.3 difference
Total Fertility Rate	1.20 children/woman	4.42 children/woman	3.22 difference
Estimated Birth Rate	6.4 per 1,000	28.8 per 1,000	22.4 difference
Aging Index (65+/0-14)	266.9%	7.6%	259.3pp difference
Population Pyramid Type	constrictive	expansive	Different types

📊 Understanding the Population Difference Chart

This visualization shows where and by how much the populations differ between Japan and Nigeria for each age group, split by gender:

Left Side (Males)

Blue = Japan has more males

Green = Nigeria has more males

Right Side (Females)

Pink = Japan has more females

Orange = Nigeria has more females

💡 How to Read: Each age group shows up to 2 bars - one on the left (male difference) and one on the right (female difference). The bar's color tells you which country has more people, and the bar's length shows by how much. For example, if you see a green bar on the left, it means Nigeria has more males in that age group.

Notable Differences (>20% variance):

Ages 0-4: Nigeria has 88.5% more people

Men: 15.3M more in Nigeria • Women: 15.0M more in Nigeria

Japan: 2.0M men, 1.9M women • Nigeria: 17.3M men, 16.9M women

Population Ratio

3.9M

34.2M

Ages 5-9: Nigeria has 85.3% more people

Men: 13.7M more in Nigeria • Women: 13.4M more in Nigeria

Japan: 2.4M men, 2.3M women • Nigeria: 16.1M men, 15.6M women

Population Ratio

4.7M

31.7M

Ages 10-14: Nigeria has 82.6% more people

Men: 12.7M more in Nigeria • Women: 12.3M more in Nigeria

Japan: 2.7M men, 2.6M women • Nigeria: 15.4M men, 14.9M women

Population Ratio

5.3M

30.3M

Ages 15-19: Nigeria has 78.9% more people

Men: 10.8M more in Nigeria • Women: 10.4M more in Nigeria

Japan: 2.9M men, 2.8M women • Nigeria: 13.7M men, 13.2M women

Population Ratio

5.7M

26.9M

Ages 20-24: Nigeria has 73.1% more people

Men: 8.5M more in Nigeria • Women: 8.2M more in Nigeria

Japan: 3.1M men, 3.0M women • Nigeria: 11.6M men, 11.2M women

Population Ratio

6.1M

22.8M

Ages 25-29: Nigeria has 66.5% more people

Men: 6.2M more in Nigeria • Women: 6.0M more in Nigeria

Japan: 3.1M men, 3.0M women • Nigeria: 9.3M men, 9.0M women

Population Ratio

6.1M

18.3M

Ages 30-34: Nigeria has 60.1% more people

Men: 4.6M more in Nigeria • Women: 4.5M more in Nigeria

Japan: 3.1M men, 3.0M women • Nigeria: 7.7M men, 7.5M women

Population Ratio

6.0M

15.2M

Ages 35-39: Nigeria has 49.6% more people

Men: 3.2M more in Nigeria • Women: 3.2M more in Nigeria

Japan: 3.3M men, 3.2M women • Nigeria: 6.5M men, 6.4M women

Population Ratio

6.5M

12.9M

Ages 40-44: Nigeria has 35.3% more people

Men: 2.0M more in Nigeria • Women: 2.0M more in Nigeria

Japan: 3.7M men, 3.6M women • Nigeria: 5.7M men, 5.6M women

Population Ratio

7.3M

11.3M

Ages 50-54: Japan has 35.2% more people

Men: 1.3M more in Japan • Women: 1.3M more in Japan

Japan: 5.0M men, 4.9M women • Nigeria: 3.7M men, 3.7M women

Population Ratio

9.9M

7.3M

Ages 55-59: Japan has 51.5% more people

Men: 1.5M more in Japan • Women: 1.4M more in Japan

Japan: 4.3M men, 4.2M women • Nigeria: 2.8M men, 2.8M women

Population Ratio

8.5M

5.6M

Ages 60-64: Japan has 78.4% more people

Men: 1.8M more in Japan • Women: 1.6M more in Japan

Japan: 3.9M men, 3.8M women • Nigeria: 2.1M men, 2.2M women

Population Ratio

7.7M

4.3M

Ages 65-69: Japan has 129.5% more people

Men: 2.1M more in Japan • Women: 2.0M more in Japan

Japan: 3.6M men, 3.7M women • Nigeria: 1.5M men, 1.6M women

Population Ratio

7.3M

3.2M

Ages 70-74: Japan has 273.1% more people

Men: 2.8M more in Japan • Women: 3.0M more in Japan

Japan: 3.8M men, 4.1M women • Nigeria: 995K men, 1.1M women

Population Ratio

7.8M

2.1M

Ages 75-79: Japan has 615.4% more people

Men: 3.4M more in Japan • Women: 4.1M more in Japan

Japan: 4.0M men, 4.7M women • Nigeria: 573K men, 642K women

Population Ratio

8.7M

1.2M

Ages 80-84: Japan has 934.0% more people

Men: 2.3M more in Japan • Women: 3.2M more in Japan

Japan: 2.6M men, 3.5M women • Nigeria: 274K men, 309K women

Population Ratio

6.0M

583K

Ages 85-89: Japan has 2086.0% more people

Men: 1.5M more in Japan • Women: 2.5M more in Japan

Japan: 1.6M men, 2.6M women • Nigeria: 86K men, 104K women

Population Ratio

4.1M

189K

Ages 90-94: Japan has 5884.1% more people

Men: 634K more in Japan • Women: 1.5M more in Japan

Japan: 649K men, 1.5M women • Nigeria: 15K men, 21K women

Population Ratio

2.2M

37K

Ages 95-99: Japan has 17668.7% more people

Men: 141K more in Japan • Women: 518K more in Japan

Japan: 143K men, 520K women • Nigeria: 1K men, 2K women

Population Ratio

663K

Ages 100+: Japan has 61565.0% more people

Men: 18K more in Japan • Women: 105K more in Japan

Japan: 18K men, 106K women • Nigeria: 53 men, 147 women

Population Ratio

123K

200

195020252025

Population Difference

-114.4M

Nigeria larger

Growth Since 1950

Japan

+42.4%

Nigeria

+537.1%

Population Ratio

1 : 1.93

Japan : Nigeria

Metric	Japan	Nigeria	Difference
Total Population	123.1M	237.5M	-48.2%
Median Age	50.8 years	19.2 years	+31.6
Youth Population (0-14)	13.8M 11.2%	96.2M 40.5%	-85.6%
Working Age (15-64)	72.3M 58.8%	134.0M 56.4%	-46.0%
Elderly Population (65+)	36.9M 30.0%	7.3M 3.1%	+406.4%
Total Dependency Ratio	70.2 per 100	77.3 per 100	-7.1
Youth Dependency Ratio	19.1 per 100	71.8 per 100	-52.7
Old-Age Dependency Ratio	51.0 per 100	5.4 per 100	+45.6
Sex Ratio	95.2 M/100F	102.4 M/100F	-7.3
Population Structure Type	Constrictive	Expansive	Different

Total Population

Japan

123.1M

Nigeria

237.5M

Difference: -48.2%

Median Age

Japan

50.8 years

Nigeria

19.2 years

Difference: +31.6

Youth Population (0-14)

Japan

13.8M

11.2%

Nigeria

96.2M

40.5%

Difference: -85.6%

Working Age (15-64)

Japan

72.3M

58.8%

Nigeria

134.0M

56.4%

Difference: -46.0%

Elderly Population (65+)

Japan

36.9M

30.0%

Nigeria

7.3M

3.1%

Difference: +406.4%

Total Dependency Ratio

Japan

70.2 per 100

Nigeria

77.3 per 100

Difference: -7.1

Youth Dependency Ratio

Japan

19.1 per 100

Nigeria

71.8 per 100

Difference: -52.7

Old-Age Dependency Ratio

Japan

51.0 per 100

Nigeria

5.4 per 100

Difference: +45.6

Sex Ratio

Japan

95.2 M/100F

Nigeria

102.4 M/100F

Difference: -7.3

Note: Dependency ratios represent the number of dependents (youth + elderly) per 100 working-age individuals. Higher ratios indicate greater economic burden on the working population.

Current Gap

3.22

births per woman

Below Replacement Level

Japan

Population decline risk

2030 Projection Gap

2.92

Nigeria above replacement

Note: The replacement fertility rate of 2.1 is the level at which a population exactly replaces itself from one generation to the next.Both countries are experiencing demographic transitions as they develop economically. Countries below 2.1 face potential population decline without immigration, while those above 2.1 continue growing naturally.

🏆

Historic Milestone: 2023

Nigeria became the world's most populous country, ending Japan's centuries-long reign

Japan: 75-Year Journey

1950 Population:86M

2025 Population:123M

Total Growth:+37M (42.4%)

Peak Year:2008 (Declining since)

Nigeria: 75-Year Journey

1950 Population:37M

2025 Population:238M

Total Growth:+200M (537.1%)

Projected Peak:Still growing

Growth Rate by Period

1950-1975

Japan: 1.09%/yr

Nigeria: 2.15%/yr

1975-2000

Japan: 0.46%/yr

Nigeria: 2.80%/yr

2000-2025

Japan: -0.13%/yr

Nigeria: 2.56%/yr

Frequently Asked Questions

India officially overtook China as the world's most populous country in April 2023, according to United Nations estimates. This historic shift ended China's long reign as the world's most populous nation, a position it had held for centuries. As of 2025, India has 237.5 million people compared to China's 123.1 million, a gap of 114.4 million people.