Kanagawa神奈川県
Kaisei 開成町
Data last updated:
Kaisei, Kanagawa, Japan has a population of 18,582 (2025 national census). IPSS projections estimate 19,146 by 2030 and 18,790 by 2050 (an increase of about 2.5% from 2020), with the share of residents aged 65+ rising from 26.1% in 2020 to 35.6%.Sources: Japan Census (Statistics Bureau), IPSS Regional Population Projections (2023)
2025
(Census)
18,582
2030
(Projection)
19,146
▲ +4.5%
2040
(Projection)
19,155
▲ +4.5%
2050
(Projection)
18,790
▲ +2.5%
Change vs. 2020 census
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Other municipalities in Kanagawa (神奈川県)
Data Sources
- Portal Site of Official Statistics of Japan (e-Stat)（https://www.e-stat.go.jp/）
- National Institute of Population and Social Security Research (IPSS), Regional Population Projections (2023 ed.)
* This service uses the e-Stat API but its content is not guaranteed by the Japanese government.
Kaisei Population Table (1980–2050)
Population by year: national census results (restated to current municipal boundaries) and IPSS (2023) projections based on the 2020 census.
| Year | Population | vs 2020 | Type |
|---|---|---|---|
| 1980 | 10,673 | ▼ -41.8% | Census |
| 1985 | 11,227 | ▼ -38.7% | Census |
| 1990 | 11,941 | ▼ -34.9% | Census |
| 1995 | 12,698 | ▼ -30.7% | Census |
| 2000 | 13,396 | ▼ -26.9% | Census |
| 2005 | 15,123 | ▼ -17.5% | Census |
| 2010 | 16,369 | ▼ -10.7% | Census |
| 2015 | 17,013 | ▼ -7.2% | Census |
| 2020 | 18,329 | — | Census |
| 2025 | 18,582 | ▲ +1.4% | Census |
| 2030 | 19,146 | ▲ +4.5% | Projection |
| 2035 | 19,208 | ▲ +4.8% | Projection |
| 2040 | 19,155 | ▲ +4.5% | Projection |
| 2045 | 19,009 | ▲ +3.7% | Projection |
| 2050 | 18,790 | ▲ +2.5% | Projection |
About Kaisei
Overview
Kaisei (開成町) is a municipality in Kanagawa, Japan, with a population of 18,582 as of 2025.
Population Projection of Kaisei
According to projections by Japan's National Institute of Population and Social Security Research (IPSS), Kaisei's population is expected to reach 19,146 by 2030 (+4.5%), 19,155 by 2040 (+4.5%), and 18,790 by 2050 (+2.5%). Kaisei is among the rare Japanese municipalities projected to see population growth.
Aging Rate of Kaisei
The aging rate (percentage of residents aged 65 and over) is 26.1% as of 2020 and is projected to rise to 35.6% by 2050. The aging rate will remain below the most severe Japanese averages.
National Comparison
Kaisei's demographic trajectory is similar to the national average.
National and Prefectural Rank
- Population decline rate: Ranked #1831 out of 1903 municipalities nationwide.
- Aging rate in 2050: Ranked #1572 out of 1903 nationwide.
- Population size: Ranked #1095 out of 1917 nationwide.
- Related: National rankings / All municipalities in Kanagawa
Earnings in Kanagawa (神奈川県): Average salary in Kanagawa (神奈川県) by age, gender and company sizejpsalary / MHLW Basic Survey on Wage Structure