Topics
Okayama, 
Japan
817,266 people lived in Okayama in 2025. It is the 643rd largest of the world's 12,138 cities, and the 11th largest in Japan.
That figure counts the whole built-up area, not the area Okayama governs, so it may be far from the number the city publishes about itself. How the UN measures a city.
Verified 2026-09-30 · 73 canaries
People · every five years · 1975 to 2050
How Okayama grew
Count 10 people in Okayama in 1975 and the same count gives 50.1 in 2025.
On the UN's projection it will have 671,251 people in 2050. It passed 250,000 people between 1985 and 1990.
projected (after 2025) · how sure the UN is: high moderate low
How to read this: one column every five years, 1975 to 2050; its height is the number of people. Hatched columns are the UN's projection. The thin strip beneath says how sure the UN is of each figure: the stronger the colour, the surer. A blank means the place was not on the UN's list of cities that year.
People · your family's years · 1975 to 2050
Okayama through your family’s years
Put in the years your family were born. You’ll see how many people lived in Okayama in each of those years, and when each of them turned 30.
Japan · every city · 2025
Where it is
How to read this: every dot is one of the 137 cities in Japan in 2025, and a dot's area is how many people live there, the biggest being Tokyo. The ringed dot in colour is Okayama; the grey dots are the rest. The outlines around them are neighbouring countries.
Area and built-up land · km²
How much land it covers
In 2025, Okayama covered 315 km², and buildings, roads and other built-up land covered 84 km² of it. That is 103 m² of built-up land for each person, about a square 10 by 10 metres. Since 1975, its built-up land has grown to 3.8 times its size, and its people are 5 times as many.
How to read this: pale is the whole of the city's land; the stronger square inside it is what is actually built on. The three are drawn to the same scale, so a larger square really is more land, and hatching means the year is the UN's projection rather than a count.
Of every 100 people in Japan
Its share of Japan
Of every 1,000 people in Japan in 2025, 7 lived in Okayama, which is 817,266 people.
How to read this: 1,000 squares stand for everyone in Japan, one square for every 1,000th person. Count the coloured ones and you have Okayama's share; the grey remainder live somewhere else in the country.
Ranked by people · 2025
Cities of a similar size
In the world, 2025
- 639 Huangshi China821,445
- 640 Vellore India820,103
- 641 Kolhapur India819,671
- 642 Porto-Novo Benin818,617
- 643 Okayama817,266
- 644 Qom Iran815,416
- 645 Zakho Iraq814,526
- 646 Munger India814,325
- 647 Nasiriyah Iraq813,799
In Japan, 2025
- 428 Kitakyushu1,206,731
- 435 Hiroshima1,185,788
- 484 Naha1,060,017
- 515 Nara993,952
- 643 Okayama817,266
- 843 Kumamoto641,185
- 978 Otsu559,798
- 1041 Kanazawa533,682
- 1124 Himeji494,064
How to read this: the figure in front of a name is where that city stands among the 12,138 cities the UN counted in 2025, and each bar is its people, on one scale per list. Numbers are missing where a city has fewer than 300,000 people and so has no page of its own.
Apparatus
Sources and method
The figures for Okayama are the UN's own, at five-year steps: an estimate for each of 1975 to 2025, then projection to 2050. Projected years are drawn hatched, and the UN publishes no range of uncertainty for a city. What a city means here, how the UN measures one, and why that number can differ from the one Okayama publishes about itself: how the figures here are put together.
Sources: UN WUP 2025 · Natural Earth · flag-icons. Every source, its licence and how to cite it →
Verified 2026-09-30 · 73 canaries