PopulationPyramids
UN World Population Prospects Data Visualized

Japan vs South Korea: Population Comparison 2026

Japan has 70,827,343 more people than South Korea (2.4× as many): 122.4 million vs 51.6 million in 2026. Median age is 50.2 in Japan and 46.2 in South Korea; fertility is 1.23 vs 0.76 children per woman.

Japan

2026
0
people
Median age
50.2
Fertility (TFR)
1.23
Working age (15–64)
58.8%
Trend
Declining (-0.55%)

South Korea

2026
0
people
Median age
46.2
Fertility (TFR)
0.76
Working age (15–64)
68.7%
Trend
Declining (-0.13%)

Population pyramids, 2026

Total Population

Japan

122.4M

vs

South Korea

51.6M

Youth (0-14)

Japan

11.0%

vs

South Korea

9.8%

Elderly (65+)

Japan

30.2%

vs

South Korea

21.4%

Where the two pyramids differ

The pyramids are overlaid so you can read the difference by age and sex: the longer bar in each band marks the country with more people of that age.

📊 Understanding the Population Difference Chart

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

Left Side (Males)

Blue = Japan has more males

Green = South Korea has more males

Right Side (Females)

Pink = Japan has more females

Orange = South Korea 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 South Korea has more males in that age group.

Notable Differences (>20% variance):

Ages 0-4: Japan has 210.7% more people
Men: 1.3M more in Japan • Women: 1.3M more in Japan
Japan: 2.0M men, 1.9M women • South Korea: 635K men, 603K women
Population Ratio
3.8M
1.2M
Ages 5-9: Japan has 181.3% more people
Men: 1.5M more in Japan • Women: 1.4M more in Japan
Japan: 2.3M men, 2.2M women • South Korea: 818K men, 779K women
Population Ratio
4.5M
1.6M
Ages 10-14: Japan has 132.4% more people
Men: 1.5M more in Japan • Women: 1.4M more in Japan
Japan: 2.7M men, 2.5M women • South Korea: 1.1M men, 1.1M women
Population Ratio
5.2M
2.2M
Ages 15-19: Japan has 141.0% more people
Men: 1.7M more in Japan • Women: 1.6M more in Japan
Japan: 2.9M men, 2.7M women • South Korea: 1.2M men, 1.1M women
Population Ratio
5.6M
2.3M
Ages 20-24: Japan has 137.6% more people
Men: 1.8M more in Japan • Women: 1.8M more in Japan
Japan: 3.1M men, 3.0M women • South Korea: 1.3M men, 1.2M women
Population Ratio
6.2M
2.6M
Ages 25-29: Japan has 83.5% more people
Men: 1.4M more in Japan • Women: 1.4M more in Japan
Japan: 3.1M men, 3.0M women • South Korea: 1.8M men, 1.6M women
Population Ratio
6.1M
3.3M
Ages 30-34: Japan has 63.9% more people
Men: 1.1M more in Japan • Women: 1.2M more in Japan
Japan: 3.1M men, 2.9M women • South Korea: 2.0M men, 1.7M women
Population Ratio
6.0M
3.7M
Ages 35-39: Japan has 90.5% more people
Men: 1.5M more in Japan • Women: 1.5M more in Japan
Japan: 3.2M men, 3.1M women • South Korea: 1.8M men, 1.6M women
Population Ratio
6.3M
3.3M
Ages 40-44: Japan has 94.4% more people
Men: 1.7M more in Japan • Women: 1.8M more in Japan
Japan: 3.6M men, 3.5M women • South Korea: 1.9M men, 1.8M women
Population Ratio
7.1M
3.7M
Ages 45-49: Japan has 106.6% more people
Men: 2.1M more in Japan • Women: 2.1M more in Japan
Japan: 4.1M men, 4.0M women • South Korea: 2.0M men, 1.9M women
Population Ratio
8.1M
3.9M
Ages 50-54: Japan has 134.7% more people
Men: 2.8M more in Japan • Women: 2.8M more in Japan
Japan: 4.9M men, 4.9M women • South Korea: 2.1M men, 2.1M women
Population Ratio
9.8M
4.2M
Ages 55-59: Japan has 103.4% more people
Men: 2.3M more in Japan • Women: 2.2M more in Japan
Japan: 4.5M men, 4.4M women • South Korea: 2.2M men, 2.2M women
Population Ratio
8.9M
4.4M
Ages 60-64: Japan has 89.9% more people
Men: 1.9M more in Japan • Women: 1.8M more in Japan
Japan: 3.9M men, 3.8M women • South Korea: 2.0M men, 2.0M women
Population Ratio
7.7M
4.1M
Ages 65-69: Japan has 86.5% more people
Men: 1.7M more in Japan • Women: 1.6M more in Japan
Japan: 3.6M men, 3.6M women • South Korea: 1.9M men, 2.0M women
Population Ratio
7.2M
3.9M
Ages 70-74: Japan has 175.6% more people
Men: 2.3M more in Japan • Women: 2.4M more in Japan
Japan: 3.6M men, 3.9M women • South Korea: 1.3M men, 1.4M women
Population Ratio
7.5M
2.7M
Ages 75-79: Japan has 373.7% more people
Men: 3.2M more in Japan • Women: 3.8M more in Japan
Japan: 4.0M men, 4.8M women • South Korea: 835K men, 1.0M women
Population Ratio
8.8M
1.9M
Ages 80-84: Japan has 358.8% more people
Men: 2.0M more in Japan • Women: 2.7M more in Japan
Japan: 2.6M men, 3.5M women • South Korea: 529K men, 786K women
Population Ratio
6.0M
1.3M
Ages 85-89: Japan has 415.7% more people
Men: 1.4M more in Japan • Women: 2.1M more in Japan
Japan: 1.6M men, 2.7M women • South Korea: 276K men, 559K women
Population Ratio
4.3M
835K
Ages 90-94: Japan has 543.6% more people
Men: 600K more in Japan • Women: 1.3M more in Japan
Japan: 683K men, 1.6M women • South Korea: 83K men, 270K women
Population Ratio
2.3M
352K
Ages 95-99: Japan has 677.9% more people
Men: 141K more in Japan • Women: 472K more in Japan
Japan: 153K men, 551K women • South Korea: 12K men, 79K women
Population Ratio
704K
91K
Ages 100+: Japan has 861.0% more people
Men: 18K more in Japan • Women: 95K more in Japan
Japan: 18K men, 108K women • South Korea: 684 men, 12K women
Population Ratio
126K
13K

Demographic comparison, 2026

IndicatorJapanSouth KoreaDifference
Population (2026)122,427,73151,600,388Japan has 70.8 million more (2.4×)
Change 2025–2026-0.5% (Declining)-0.1% (Declining)
Median age (2026)50.246.2Japan older by 4.0 yrs
Total fertility rate1.23 — 0.87 below replacement0.76 — 1.34 below replacement
Fertility rate, 2030 (UN projection)1.260.81
Birth rate (per 1,000)6.14.8
Population 2050 (UN projection)105.1 million (-14.1%)45.1 million (-12.5%)
Peak populationPeaks 2009Peaks 2020

Differences by age group, 2026

AgeJapan (M / F)South Korea (M / F)Difference
0-41968K / 1879K635K / 603KJapan has 210.7% more people aged 0-4
5-92301K / 2192K818K / 779KJapan has 181.3% more people aged 5-9
10-142663K / 2521K1142K / 1088KJapan has 132.4% more people aged 10-14
15-192897K / 2746K1205K / 1136KJapan has 141.0% more people aged 15-19
20-243148K / 3004K1345K / 1244KJapan has 137.6% more people aged 20-24
25-293134K / 3011K1752K / 1597KJapan has 83.5% more people aged 25-29
30-343062K / 2942K1965K / 1699KJapan has 63.9% more people aged 30-34
35-393217K / 3101K1754K / 1563KJapan has 90.5% more people aged 35-39
40-443605K / 3524K1898K / 1769KJapan has 94.4% more people aged 40-44
45-494098K / 4031K2008K / 1928KJapan has 106.6% more people aged 45-49
50-544934K / 4866K2113K / 2063KJapan has 134.7% more people aged 50-54
55-594495K / 4412K2185K / 2194KJapan has 103.4% more people aged 55-59
60-643878K / 3829K2020K / 2038KJapan has 89.9% more people aged 60-64
65-693575K / 3647K1875K / 1999KJapan has 86.5% more people aged 65-69
70-743605K / 3893K1276K / 1444KJapan has 175.6% more people aged 70-74
75-794025K / 4786K835K / 1024KJapan has 373.7% more people aged 75-79
80-842574K / 3459K529K / 786KJapan has 358.8% more people aged 80-84
85-891627K / 2678K276K / 559KJapan has 415.7% more people aged 85-89
90-94683K / 1586K83K / 270KJapan has 543.6% more people aged 90-94
95-99153K / 551K12K / 79KJapan has 677.9% more people aged 95-99
100+18K / 108K1K / 12KJapan has 861.0% more people aged 100+

Frequently Asked Questions

Which has more people, Japan or South Korea?

Japan has more: 122.4 million vs 51.6 million in 2026 — 2.4× as many, 70.8 million more people.

Which country is older?

Japan, with a median age of 50.2 vs 46.2 in South Korea (2026).

Which has higher fertility?

Japan, at 1.23 children per woman vs 0.76 in South Korea. Replacement is 2.1, so both are below it.

How will Japan and South Korea compare in 2050?

By 2050 the UN projects Japan at 105.1 million (-14.1% from 2026) and South Korea at 45.1 million (-12.5%).

Are Japan and South Korea growing or shrinking?

Japan is declining (-0.5% in 2026); South Korea is declining (-0.1%).

Explore Individual Countries

Japan population pyramid→South Korea population pyramid→

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