How much CO2 does your portfolio finance each year?
$
Presets use Vanguard Target Retirement fund allocations1, the default for the majority of 401(k) participants.2
Total allocation100%
79.3
tonnes CO2e financed per year
Scope basis:
Methodology & Equations
The range shown under the headline number applies each class’s low and high intensity estimate (matrix below) to the same allocation — it is the spread of the inputs, not a statistical confidence interval. Intensities decline ~3–5% annually as grids decarbonize.
Scope 1+2 central estimates and ranges, tCO2e per $1M invested. Highlighted cells are the values in use; the Scope 3 column is the multiplier applied when the estimated Scope 3 view is on.356
Asset class
Low
Central
High
Scope 3 ×
Primary source
Bitcoin row is derived, not looked up: MtCO2e/yr network emissions6 ÷ $ T market cap9 = t per $1M. Edit either input; when the price doubles, carbon per dollar halves.
Fossil fuels: the widely quoted ~700 t/$M is a Scope 1+2+3 figure (combustion of sold products dominates). Divided by the same ×3 rule this page uses for Scope 3, that is ~233 t/$M on the Scope 1+2 basis every other row uses — so fossil and clean are compared like for like.
Carbon Intensity by Age
Financed emissions per $1M, using Vanguard target-date allocations1 as a proxy for each age cohort.
Younger investors hold 90% equities (higher intensity per dollar). The glide path shifts to bonds over time, lowering intensity—but older investors typically have more saved, increasing absolute emissions.
Calculation pipeline from inputs to financed emissions. Rendered client-side; source below for reproducibility.
graph LR
A[Investment Amount $] --> B[Allocation Weights w_i]
B --> C{For each asset class i}
C --> D[w_i x A x I_i]
D --> E[Sum = Total Financed Emissions]
F[Carbon Intensity Lookup] --> D
G[Vanguard Glide Path] --> B
H[SCF Demographics] --> I[Median Savings by Age]
I --> A
subgraph Sources
F -- MSCI/Trucost --> J[Scope 1+2 tCO2e/$M]
F -- PCAF --> J
G -- Fund Prospectus --> K[Stock/Bond Split]
H -- Fed Reserve 2022 --> L[Balance by Cohort]
end
style E fill:#e8f5e9,stroke:#1a6b3c
style J fill:#fff3cd,stroke:#92400e
style K fill:#dbeafe,stroke:#1e40af
style L fill:#fce4ec,stroke:#9e2a2a
Mermaid source
Key Findings
Younger = higher intensity/dollar. 90/10 stock/bond allocations (ages 20–40) have higher carbon intensity per dollar than 30/70 retiree portfolios, because equities are more carbon-intense than bonds.
Financed emissions ≠ intensity. Financed emissions = your share of a company’s absolute CO2. WACI = CO2 per $M revenue.3 Both matter for different decisions.
Share Your Result
My portfolio finances 79.3t CO₂/yr — 5.0× the average American's personal footprint.
Share link includes your allocation and scope basis — recipients see the same numbers. The downloaded card is 1200×630px; links to this page also carry a preview image now.
We help investors quantify financed emissions and build lower-carbon portfolios.
25 page claims graded by Continuity Check on 2026-09-08 — 23 confirmed · 1 unverifiable · 1 contradicted (a footnote label; corrected the same day)
Read the audit · Gemini on Vertex AI + Parallel Search, grounded on retrieved evidence only · the calculator’s arithmetic is covered separately by its tests
Notes & Sources
Vanguard Target Retirement Fund allocations from fund prospectuses and Vanguard Target Retirement Funds. Glide path data as of 2025.
Vanguard, How America Saves 2025. Target-date fund adoption among 401(k) participants. (The 2024 edition link used previously no longer resolves.)
