Compare · UN World Population Prospects 2024

Japan and United States, side by side

Line both places up by age in 2026. In Japan, half are older than 51; in the United States, half are older than 40.

UN estimates for mid-2023: Japan 124,370,946 people · United States 343,477,335

Japan 122 million people Half are older than 51 30 in 100 are 65 or older

United States 349 million people Half are older than 40 19 in 100 are 65 or older

How to read this: each pyramid stacks a place’s people by age — babies at the bottom, the oldest at the top, men on the left and women on the right. A wide bottom means many children; a wide top means many older people.

Compare shapes Compare sizes

Each bar is a share of its own place’s people, so a small country and a large one can be read side by side.

Year 2026 · UN projection

estimatesprojections

men women projected

Verified 2026-09-30 · 73 canaries

JPN × USA · 2026 · age groups

If each place were 100 people

Shrink each population to 100 people and count them. Dots are children under 15, filled squares are people aged 15 to 64, and open squares are people 65 and over. The picture follows the year slider above.

Japan

Children, under 15: 11
Aged 15 to 64: 59
Aged 65 and over: 30

United States

Children, under 15: 17
Aged 15 to 64: 64
Aged 65 and over: 19

JPN × USA · families and lifetimes

Children, and how long lives last

Japan is at about 1.2 children for each woman, at this year's rates; the United States is at about 1.6. Life expectancy at birth this year: about 85 years in Japan, about 80 in the United States.

Children per woman, 2026

Each figure is one child: how many children a woman would have in her lifetime at that year’s rates.

Japan 1.2

United States 1.6

The dashed line at 2.1 is about what it takes for each generation to replace the one before it, leaving migration aside.

How long a newborn can expect to live, 2026

Each block is ten years of life, if the death rates of that year stayed the same all life long.

Japan 85 years

United States 80 years

Hatched marks are UN projections (medium variant), not measurements.

JPN × USA · 1950–2100 · how many

How big, and where they are heading

There are 349 million people in the United States and 122 million in Japan: about three times as many people as Japan.

Since 1950 the two have moved differently: Japan's population is 1.4 times what it was in 1950, while the United States' population is 2.3 times what it was in 1950.

Looking ahead: Japan's population peaked in 2009, and the United States' population is still growing in 2100. In 2100: 76.8 million in Japan, 421 million in the United States (UN projection, medium).

Show the numbers

Year	Japan: people	United States: people	Japan: half older than	United States: half older than	Japan: children per woman	United States: children per woman	Japan: life expectancy	United States: life expectancy
1950	86.4433 million	154.203 million	22.3	30.0	3.62	3.09	59.3	68.1
1960	96.3997 million	180.275 million	25.7	29.3	1.98	3.73	67.7	69.8
1970	106.712 million	207.796 million	29.3	27.7	2.04	2.52	72.0	70.7
1980	118.359 million	229.859 million	32.7	30.1	1.74	1.86	76.1	73.7
1990	123.400 million	253.373 million	37.9	32.9	1.51	2.07	79.0	75.4
2000	127.028 million	281.484 million	41.8	35.3	1.35	2.03	81.2	76.8
2010	128.185 million	311.063 million	45.2	36.9	1.36	1.92	82.9	78.7
2023	124.371 million	343.477 million	50.0	39.0	1.21	1.62	84.7	79.3
2030*	119.584 million	355.650 million	52.5	40.6	1.26	1.63	85.7	80.4
2040*	112.158 million	370.209 million	54.1	41.8	1.31	1.64	87.1	81.8
2050*	105.123 million	380.847 million	53.8	42.9	1.35	1.64	88.4	83.2
2060*	98.1032 million	388.918 million	54.1	44.1	1.39	1.64	89.7	84.6
2070*	90.6118 million	398.218 million	54.6	44.7	1.42	1.64	90.9	85.8
2080*	84.7300 million	407.080 million	53.7	45.1	1.44	1.65	92.1	87.0
2090*	80.6344 million	414.458 million	53.4	45.8	1.46	1.65	93.2	88.1
2100*	76.8460 million	421.279 million	54.0	46.3	1.47	1.65	94.4	89.2

* UN projection, medium variant. People at mid-year; ages and life expectancy in years.

JPN − USA · 1950–2100 · every age

Which ages each place has more of

Each column is a year and each row an age, from babies at the bottom to 100 at the top. The shade of a cell shows which place has more of its people at that age — the key beside the picture tells you which shade is Japan and which is the United States, and the in-between shade means the same. Because it compares shares, a small place and a large one can be compared fairly.

236 countries · 1950–2100

Where they sit among all countries

Every country in the world, every year from 1950 to 2100. The grey cloud shows where most countries are; Japan is drawn in solid blue squares and the United States in open orange squares, so you can see whether each is ahead of the crowd, behind it or in the middle.

More comparisons

Keep exploring

Each place on its own: Japan · United States. Or pick any two places with the boxes at the top of this page.

Other comparisons

Apparatus

Sources and method

Japan and United States are drawn here from one source and one release: the UN Population Division's World Population Prospects 2024, counted through 2023 and projected on its medium variant after that. Two places read off the same tables can be set against each other; two read off different tables cannot.

For how the median age is derived, why “100 people” can read a person high or low, and what the all-country pictures do and do not count, see the method.

There are 250 ready-made comparisons on this site. For anything else, name two places in the boxes at the top of the page.

Sources: UN WPP 2024 · flag-icons. Every source, its licence and how to cite it →

Verified 2026-09-30 · 73 canaries