Population forecast · World Bank data
Japan population forecast
Population, total
Latest · 2025
123.4M
The population of Japan is forecast at 122.7M in 12 months (2026), with an 80% range of 121.7M to 122.9M. The latest World Bank figure is 123.4M for 2025.
In 24 months (2027) and 36 months (2028) the model projects 122.3M and 121.6M (−1.4% versus 2025).
Display-only line. World Bank data is annual: the forecasts are the yearly points marked on the chart. The monthly line between them is a straight-line interpolation for display, not a monthly forecast.
- 6 monthsinterpolated · display only
- 123.0M▼ −0.3%80%: 122.5M – 123.1M
- 12 months2026
- 122.7M▼ −0.5%80%: 121.7M – 122.9M
- 24 months2027
- 122.3M▼ −0.8%80%: 120.9M – 122.8M
- 36 months2028
- 121.6M▼ −1.4%80%: 119.6M – 122.4M
Backtest · last 5 years
How accurate has this been?
| Horizon | Tests | Avg. error | Naive error | In 80% range |
|---|---|---|---|---|
| 12 months | 5 | 0.18M | 0.58M | 100% |
| 24 months | 4 | 0.29M | 1.15M | 100% |
| 36 months | 3 | 0.37M | 1.74M | 100% |
We re-ran the model as if standing at past dates, using only the data available then. Avg. error is the mean absolute gap between the median and what happened; naive assumes no change from the last value. A well-calibrated 80% range contains about 80% of outcomes. Annual series have few test points, so treat these as rough. Methodology
Source data
Recent values
| Year | Value | Change |
|---|---|---|
| 2025 | 123.4M | −0.49% |
| 2024 | 124.0M | −0.43% |
| 2023 | 124.5M | −0.49% |
| 2022 | 125.1M | −0.44% |
| 2021 | 125.7M | −0.46% |
| 2020 | 126.3M | −0.29% |
| 2019 | 126.6M | −0.14% |
| 2018 | 126.8M | −0.13% |
| 2017 | 127.0M | −0.08% |
| 2016 | 127.1M | −0.05% |
About this forecast
- Source
- World Bank, World Development Indicators · series SP.POP.TOTL
- Data through
- 2025 · 66 observations
- Forecast updated
- Sep 28, 2026
- Model
- TimesFM 2.5 (Google Research, Apache-2.0), zero-shot
More forecasts for Japan
Japan overviewOther population forecasts
All 40Statistical model, not financial advice. This forecast is generated automatically from public data; the 80% range means outcomes are expected outside it about one time in five. Don't make financial decisions based only on it.
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