Size My Habit

Driving & Fuel: Hours Driving vs Time Spent Driving

See how your driving & fuel habit scales when comparing hours driving to time spent driving. 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

Your Habit Scale

See how your consumption adds up over time.
Time PeriodEquivalent in Time Spent Driving
1 Year10.8 days
5 Years54.2 days
25 Years270.8 days

How It's Calculated

  • 1. Your input: 5 Hours Driving per week.
  • 2. We calculate the total hours you spend driving in a year: 5 hours/week × 52 weeks/year = 260 hours.
  • 3. We then convert this to full 24-hour days by dividing by 24.
  • 4. The table shows this accumulated time over 1, 5, and 25 years.

Why It's Important

We often think of our commute in minutes, but seeing it add up to 10.8 full 24-hour days over just one year can be staggering. This isn't just time on the road; it's a significant, measurable portion of your life spent behind the wheel.

Why does this matter? Quantifying your cumulative driving time provides a powerful new perspective on your lifestyle. It transforms an abstract routine into a tangible block of your time budget. This insight can be a catalyst for re-evaluating work-life balance, exploring the benefits of remote work, or simply appreciating the value of time saved through more efficient travel.

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.