Commute Emissions Calculator Formula
Understand the math behind the commute emissions calculator. Each variable explained with a worked example.
Formulas Used
Annual Commute CO2
co2_tons = co2_lbs / 2204.6Annual Commute Distance
annual_distance = annual_milesAnnual Fuel Used
fuel_used = annual_gallonsVariables
| Variable | Description | Default |
|---|---|---|
commute_miles | One-Way Commute Distance(miles) | 15 |
days_per_week | Commute Days per Week | 5 |
weeks_per_year | Work Weeks per Year | 50 |
mpg | Vehicle Fuel Economy(mpg) | 28 |
annual_miles | Derived value= commute_miles * 2 * days_per_week * weeks_per_year | calculated |
annual_gallons | Derived value= annual_miles / mpg | calculated |
co2_lbs | Derived value= annual_gallons * 19.6 | calculated |
How It Works
How to Calculate Commute Emissions
Your daily commute can be a significant part of your personal carbon footprint.
Formula
Annual CO2 = (Distance * 2 * Days/Week * Weeks/Year) / MPG * 19.6 lbs/gallon / 2,204.6
Multiply one-way distance by 2 for round trip, divide total miles by fuel economy to get gallons, then multiply by 19.6 lbs CO2 per gallon.
Worked Example
A 15-mile one-way commute, 5 days/week, 50 weeks/year, in a 28 mpg car.
- 01Annual miles: 15 * 2 * 5 * 50 = 7,500 miles
- 02Gallons used: 7,500 / 28 = 267.9 gallons
- 03CO2: 267.9 * 19.6 = 5,250 lbs = 2.38 metric tons/year
Frequently Asked Questions
How much CO2 does an average commute produce?
The average US commute of 16 miles each way at 28 mpg produces roughly 2.5 metric tons of CO2 per year.
How much would carpooling reduce emissions?
Carpooling with one other person cuts per-person commute emissions by 50%. A four-person carpool cuts it by 75%.
What about public transit emissions?
Public buses emit about 0.06 lbs CO2 per passenger-mile, and rail about 0.02 lbs, far lower than solo driving.
Ready to run the numbers?
Open Commute Emissions Calculator