How Big Is the US Defense Budget? $929.2bn in 2025
The United States spent an estimated $929.2bn on its military in 2025, according to SIPRI data — 3.12% of GDP and roughly a third of all global military spending.
Key takeaways
- The US spent $929.2bn on its military in 2025, according to SIPRI data — the largest total of any country.
- That figure equals 3.12% of US GDP and 33.911% of world military spending in 2025.
- US spending fell 7.5% year-over-year in 2025, and 2025 spending is 12.5% below its 2010 peak of $1,061.7bn.
- Over 5 and 10 years, spending has been roughly flat (-0.3% and 1.03% CAGR respectively).
- The SIPRI figure differs from official US defense budget totals because of different accounting definitions, not a data error.
Verdict
SIPRI data puts US military spending at $929.2bn in 2025, or 3.12% of GDP and 33.911% of world military spending — the largest single-country total in the dataset. This is the SIPRI constant-dollar measure specifically; it will not match national-budget or NATO-definition totals reported elsewhere.
At a glance
| 2025 military spending | $929.2bnSIPRI constant 2024 USD |
|---|---|
| Share of GDP | 3.12% |
| World rank | #1 |
| Share of world total | 33.911% |
| Year-over-year change | -7.5% |
| 2010 peak | $1,061.7bn |
SIPRI's constant-dollar data puts United States military spending at $929.2bn in 2025 — equivalent to 3.12% of GDP and the largest military budget of any country in the dataset.
01 How big is the US defense budget in 2025?
According to SIPRI's country-level military expenditure data, the United States spent $929.2bn in 2025, measured in constant 2024 US dollars. That figure ranks the US first among all countries tracked by SIPRI, and it is the number this page uses throughout — not the headline "national defense budget" total reported in US congressional or Pentagon documents, which is built on different accounting rules (see below).
| Metric | Value |
|---|---|
| Military spending, 2025 | $929.2bn |
| Share of GDP | 3.12% |
| World rank | 1 |
| Share of world total | 33.911% |
02 US spending as a share of GDP and world total
$929.2bn is equivalent to 3.12% of US GDP in 2025. That single ratio is the standard way analysts compare defense burdens across countries of very different sizes, since raw dollar totals don't account for the size of the underlying economy funding them.
The United States also accounts for 33.911% of world military spending in 2025 — close to one in every three dollars spent on the military worldwide that year was spent by the United States.
03 How the US budget has changed: year-over-year and 5/10-year trends
US military spending fell 7.5% year-over-year in 2025 in constant-dollar terms. Looking further back, spending has been essentially flat over the medium term: the five-year compound annual growth rate is -0.3%, while the ten-year compound annual growth rate is a modest 1.03% per year.
Those trend lines sit well below the all-time high. 2025 spending is 12.5% below its 2010 peak of $1,061.7bn (constant 2024 dollars) — a gap of roughly $132.5bn. The gap reflects the drawdown from the Iraq and Afghanistan war years rather than any single recent policy shift, and the 2025 year-over-year decline should be read against that longer, largely flat trajectory rather than as an isolated data point.
| Period | Change |
|---|---|
| 2024 → 2025 (year-over-year) | -7.5% |
| 5-year CAGR | -0.3% |
| 10-year CAGR | 1.03% |
| 2025 vs. 2010 peak ($1,061.7bn) | -12.5% |
04 Why this number differs from the official US defense budget figure
Readers who follow US budget coverage will often see a different, larger number quoted for "defense spending" — sometimes above $850bn or even $1 trillion depending on the year and the source. SIPRI's $929.2bn figure is not wrong relative to those numbers; it is answering a different, more internationally comparable question.
- Definition scope — SIPRI's military expenditure measure follows a standardized international definition designed to be comparable across countries, which does not always align one-to-one with the line items in a US appropriations bill.
- Constant-dollar adjustment — SIPRI reports figures in constant 2024 US dollars to strip out inflation, so year-to-year and country-to-country comparisons aren't distorted by price changes. Nominal, current-year US budget figures are not inflation-adjusted in the same way.
- NATO's own definition — NATO publishes a separate defense-spending series using its own accounting conventions, which also diverges from both the SIPRI figure and the US national budget total.
Because SIPRI, NATO, and US national budget documents each use different accounting boundaries, their totals for "US defense spending" in the same year are not directly interchangeable. This page uses the SIPRI figure throughout.
05 Data source and methodology
The $929.2bn figure, the 3.12% GDP ratio, the 33.911% world-share figure, and the year-over-year and CAGR trends come directly from SIPRI's country-level military expenditure dataset for the United States in 2025. All dollar figures are in constant 2024 US dollars unless otherwise noted. For the full time series and underlying detail, see the United States defense budget profile.
Frequently Asked Questions
- How big is the US defense budget in 2025?
- SIPRI data puts it at $929.2bn in 2025, or 3.12% of GDP — the largest military expenditure total of any country that year.
- What share of world military spending does the US account for?
- 33.911% of world military spending in 2025, according to SIPRI's country-level data.
- Is US military spending going up or down?
- It fell 7.5% year-over-year in 2025 and is essentially flat over the medium term (-0.3% 5-year CAGR, 1.03% 10-year CAGR), and 2025 spending is 12.5% below its 2010 peak of $1,061.7bn.
- Why does SIPRI's figure differ from the US defense budget reported in the news?
- SIPRI uses a standardized, inflation-adjusted (constant 2024 USD) definition designed for cross-country comparison, which differs from the accounting boundaries used in US appropriations documents or NATO's own defense-spending definition.
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.