A cohort projection that decomposes the change in each country's military-age male population into its three drivers — aging (cohorts entering at the bottom vs. exiting at the top), migration, and combat deaths. Base year structure: UN World Population Prospects 2024. Every assumption is a slider — drag to test scenarios.
• Negative migration = net return (e.g. refugees / émigrés coming home — likely once the war ends).
• Pool = living men in the age band. Combat wounded who survive stay in the pool (still alive), so they are not subtracted — even though many are removed from the fight. Toggle this view of "lost to the fight" by raising combat deaths to approximate killed + permanently disabled.
• Entrants through 2042 are people already born (aged 0–17 in 2024) — that part of the decline is locked in regardless of policy. Only 2043+ depends on the fertility slider.
• Attrition is applied proportionally across ages within the band; combat skews younger in reality.
• Ukraine's 2024 base (37.9M) is a WPP estimate; ~5–6M refugees abroad mean the in-country pool may be smaller than shown.
Solid = full scenario (demographics + migration + combat). Dashed = same world with no combat. The gap between them is the war's marginal toll on the living male pool.
| Age structure | UN World Population Prospects 2024, single-year cohorts interpolated from 5-year male bands (via populationpyramid.net). |
| Russia combat deaths | Mediazona + Meduza + BBC Russian probate-registry method: ~352,000 Russian men killed end-2022→end-2025; 2025 the deadliest year. Implies a recent run-rate near 100k/yr (default). |
| Ukraine combat deaths | Estimates diverge widely: Zelensky cited ~46k (2024) then higher; CSIS put deaths at 60k–140k. Default 35k/yr is a mid forward run-rate; drag to your prior. |
| Russia migration | 2022 mobilization exodus ≈ 650k–900k left, ~650k still abroad (The Bell; demographer A. Raksha). Forward net flow is small and could reverse — default +50k/yr out. |
| Ukraine migration | Martial law bars men 18–60 from leaving, so wartime net outflow of military-age men is small; a large return is plausible post-war (set slider negative). |
Sources: Mediazona/Meduza 352k · Meduza 200k+ · Casualties (overview) · The Bell émigrés · Emigration (overview) · UN WPP 2024 · Russia demography crisis. Forward projection from a 2024 base; not a forecast — a transparent calculator. Casualty figures are contested and unverifiable; treat outputs as scenario arithmetic.