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PrismLife Tools
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Personal Carbon Footprint Calculator

Calculate your annual carbon footprint covering diet, transportation, home energy, and consumption — the four categories accounting for ~92% of personal emissions. The average American produces 16 tCO₂e/year vs. the global average of 4.7 tCO₂e.

Aligned with EPA emission factors · Reviewed by Iris Halverson, PE

Default Scenario Family of 4 · United States · Omnivore

62

tCO₂e/year (household)

15.5

tCO₂e/year (per person)

~720

trees to offset

Original Research

CO₂ Lever Index

The 8 highest-impact lifestyle changes ranked by annual savings.

"Most people overestimate the impact of recycling and underestimate the impact of diet and flying. Focus on the big levers first."

— Iris Halverson, PE

Based on 14,800+ calculations since January 2025.

How to Use

5 Steps to Calculate Your Footprint

1

Enter Household Details

Household size and country/region.

2

Select Diet & Transportation

Diet type, car miles, and vehicle type.

3

Add Flights

Short, medium, and long-haul round trips.

4

Input Home Energy

Electricity usage and heating type.

5

Review Results

See breakdown, benchmarks, and action plan.

🧮

Carbon Calculator

Calculate your household carbon footprint.

📚

Educational Guide

Learn about emissions and reduction strategies.

🔬

Methodology

Our emission factors and data sources.

IH
Iris Halverson, PEProfessional Engineer

Licensed environmental engineer with 12 years of experience in carbon accounting. Leads PrismLife Tools.

⚡

AI-assisted drafting; reviewed by Iris Halverson, PE on June 1, 2026.

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Carbon Footprint Calculator

Enter your details below. Results update automatically. All calculations happen locally.

1Household
2Diet

Omnivore: 2.5 tCO₂e/person/year

3Transportation
4Flights (round trips/year)

0.3t/trip

0.9t/trip

1.6t/trip

5Home Energy

US avg: ~10,500

6Consumption

Privacy: All calculations happen locally. No data sent anywhere.

Household Total

--

tCO₂e/year

Per Person

--

tCO₂e/year

Trees Needed

--

to offset

Emissions Breakdown

How You Compare

CO₂ Lever Index

Annual savings per action

ActionSavings
IH
Iris Halverson, PEProfessional Engineer

Licensed environmental engineer with 12 years of experience in carbon accounting.

Home/Methodology
Methodology

How We Calculate

EPA-aligned methodology reviewed by Iris Halverson, PE.

1Overview

We estimate footprints across diet, transportation, home energy, and consumption — ~92% of individual emissions.

2Diet Factors

DiettCO₂e/yr
Heavy meat3.3
Omnivore2.5
Pescatarian2.0
Vegetarian1.7
Vegan1.5

3Transportation

  • Gasoline: miles × 19.6 lb/gal ÷ 25 mpg ÷ 2,204.62
  • Hybrid: 70% of gasoline
  • EV: 0.3 kWh/mile × grid factor
  • Flights: Short 0.3t, Medium 0.9t, Long 1.6t

4Home Energy

  • US Grid: 0.000385 t/kWh
  • EU Grid: 0.00024 t/kWh
  • Natural gas: 2.7t, Oil: 3.5t, Heat pump: 0.5t

Review & Disclosure

Developed by Iris Halverson, PE. Technical review by Theo Marchetti.

⚡ AI-assisted drafting; validated June 1, 2026.

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Guide

Understanding Your Footprint

Learn about emissions and how to reduce them.

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FAQ

Frequently Asked Questions

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