Japan Defense Spending Increase: 2021–2025 (+40.7%)
Japan's military expenditure grew 40.7%, from $42.3bn in 2021 to $59.5bn in 2025, in SIPRI constant 2024 US dollars.
Key takeaways
- Japan's defense spending rose 40.7%, from $42.3bn in 2021 to $59.5bn in 2025, in SIPRI constant 2024 US dollars.
- Japan's defense spending as a share of GDP rose by 0.38 percentage points over the same period.
- The 40.7% figure is our calculation from SIPRI country-level data, not a total SIPRI itself publishes.
Verdict
Japan's defense spending rose 40.7%, from $42.3bn in 2021 to $59.5bn in 2025, in SIPRI constant 2024 US dollars, alongside a 0.38 percentage-point rise in its GDP share. These change figures are defensebudget.org's calculation from SIPRI country-level data, not a total SIPRI itself publishes.
At a glance
| 2021 spending | $42.3bnSIPRI constant 2024 USD |
|---|---|
| 2025 spending | $59.5bnSIPRI constant 2024 USD |
| Change, 2021–2025 | +40.7%Our calculation from SIPRI data |
| GDP share change | +0.38 points2021 to 2025 |
Japan's defense spending rose to $59.5bn in 2025, up 40.7% from $42.3bn in 2021, according to SIPRI constant 2024 US dollar military expenditure data (data as of 2026-08-13).
01 Japan's defense spending in 2025: the headline number
Japan spent $59.5bn on defense in 2025, compared with $42.3bn in 2021, in SIPRI constant 2024 US dollars. That is a 40.7% increase over the four-year span — a real-terms figure, meaning it already accounts for inflation and is not simply a product of currency movements or price growth. For readers tracking Japan defense budget trends year to year, this page compares the two most recent SIPRI data points available for Japan: 2021 and 2025.
| Year | Defense spending | Change from 2021 |
|---|---|---|
| 2021 | $42.3bn | — |
| 2025 | $59.5bn | +40.7% |
02 The 2021–2025 trajectory
Because both figures are expressed in constant 2024 US dollars, the comparison isolates real changes in purchasing power and strips out the effect of yen depreciation or US dollar inflation over the period — the 40.7% increase reflects actual growth in resources allocated to defense, not currency noise.
03 Spending as a share of GDP: +0.38 points
Alongside the dollar increase, Japan's defense spending as a share of its GDP moved up by 0.38 percentage points between 2021 and 2025. A GDP-share measure matters alongside the dollar figure because it shows whether military spending is growing faster than the economy as a whole, rather than simply tracking overall economic expansion — a 0.38 point shift indicates defense spending outpaced GDP growth over the period, not merely kept pace with it.
The dollar totals and the four-year change figures on this page are our calculation from SIPRI country-level data, not a total SIPRI itself publishes as a single figure. All figures are expressed in constant 2024 US dollars.
04 Methodology and data sourcing
- Source — SIPRI Military Expenditure Database, country-level series for Japan.
- Currency basis — figures are in constant 2024 US dollars, which adjusts for inflation and holds the exchange rate fixed to a single reference year so that year-to-year comparisons reflect real spending changes.
- Comparison window — 2021 to 2025, the two endpoints used to compute the 40.7% change and the 0.38 percentage-point GDP-share shift cited above.
- Calculation — the percentage change and GDP-share delta are calculated by defensebudget.org from SIPRI's underlying country data; they are not figures SIPRI itself publishes as a packaged total.
Frequently Asked Questions
- How much has Japan's defense spending increased since 2021?
- Japan's defense spending increased 40.7%, from $42.3bn in 2021 to $59.5bn in 2025, in SIPRI constant 2024 US dollars.
- What is Japan's defense budget in 2025?
- Japan's defense budget was $59.5bn in 2025, in SIPRI constant 2024 US dollars.
- How much did Japan's defense spending grow as a share of GDP?
- Japan's defense spending as a share of GDP rose by 0.38 percentage points between 2021 and 2025.
- Is the 40.7% figure published directly by SIPRI?
- No — it is defensebudget.org's calculation from SIPRI's country-level data for Japan, not a total SIPRI itself publishes.
defensebudget.org
Defense spending data, sourced from SIPRI
defensebudget.org tracks military expenditure for 160 countries using the SIPRI Military Expenditure Database. Pages are generated from that dataset and reviewed before publication.