Size My Habit

Driving & Fuel: Litres of Fuel vs Trees for CO₂ Offset (annual)

See how your driving & fuel habit scales when comparing litres of fuel to trees for co₂ offset (annual). Your commute is an epic journey. Convert your driving miles into trips around the Earth or find out how many trees are needed to offset your CO₂.

Size My Driving & Fuel

(Global average ~110 or 2 tanks of fuel)

Your Habit Scale

See how your consumption adds up over time.
Time PeriodEquivalent in Trees for CO₂ Offset (annual)
1 Year145.2 trees
5 Years726 trees
25 Years3,630 trees

How It's Calculated

  • 1. Your input: 110 Litres of Fuel per month.
  • 2. We assume your vehicle uses gasoline, which produces approximately 2.31 kg of CO₂ (≈ 5.09 lbs) per litre burned.
  • 3. A mature tree can absorb about 21 kg of CO₂ (≈ 46.3 lbs) per year.
  • 4. The calculation estimates your total CO₂ emissions over time and divides it by a tree's annual absorption rate to find the number of trees needed for a carbon offset.

Why It's Important

To balance the carbon scales, your annual driving would require approximately 145.2 trees working for a full year to absorb the equivalent CO₂ emissions. It's like you have a personal, invisible forest that needs to be planted each year just to offset your time on the road!

This is a crucial comparison because it directly connects your driving habit to a tangible, natural solution. It's a clear and simple metric for your personal carbon footprint from transportation. This visualization isn't meant to stop you from driving, but to powerfully illustrate the environmental cost of vehicle emissions and encourage awareness around carbon offsetting and the importance of sustainable choices.

Do you need help with your habit? See our list of international helplines and resources.

The Science Behind It

Fuel consumption from driving contributes significantly to personal and global carbon footprints. SizeMyHabit’s Driving Fuel Calculator converts kilometers or miles driven and fuel quantity into CO₂ emissions, fuel economy metrics, and resource impact—drawing on combustion chemistry and environmental engineering.

1. Combustion Chemistry & CO₂ Production

Burning one liter of gasoline yields approximately 2.31 kg of CO₂, while diesel produces 2.68 kg/L, based on stoichiometric reaction C₈H₁₈ + 12.5 O₂ → 8 CO₂ + 9 H₂O. The calculator uses vehicle-specific fuel economy data (L/100 km or mpg) to compute total emissions per trip.

2. Life-Cycle Emissions

Tailpipe CO₂ accounts for about 75% of a vehicle’s life-cycle greenhouse-gas emissions; the remaining 25% stems from fuel extraction, refining, and distribution. Our tool adds a 1.3× multiplier to tailpipe CO₂ to approximate full life-cycle impact.

3. Fuel Efficiency & Driving Behavior

Real-world driving conditions (speed, acceleration, load) influence fuel efficiency. Each 10 km/h increase above 90 km/h can raise fuel consumption by 10–20% due to aerodynamic drag. The calculator’s “trip profile” option adjusts emissions estimates based on typical urban vs. highway driving.

4. Alternative Fuels & Electrification

Electric vehicles (EVs) produce zero tailpipe emissions, but upstream electricity generation can vary widely. In regions with 50 g CO₂/kWh grid intensity, an EV uses ~15 kWh per 100 km, equating to 0.75 kg CO₂/100 km—one-tenth of an efficient gasoline car. SizeMyHabit allows users to compare petrol, diesel, and electric modes side by side.

5. Behavioral Feedback & Modal Shift

Providing personalized CO₂ feedback increases the likelihood of behavioral change: drivers who see their emissions per trip reduce annual mileage by up to 5% and shift 10% of trips to public or active transport. Visualizing “trees needed to offset” reinforces the impact of small choices.