Travel, Auto & Lifestyle
Carbon Footprint Calculator
Carbon Footprint: carbon Footprint Calculator multiplies your electricity, gas, car travel and flights by standard emission factors to estimate annual CO₂e in kilograms. Worked through below with real figures, and the calculator repeats the working on your own inputs — free, on-device, instant.
Carbon Footprint Calculator lets you estimate your carbon footprint in seconds: enter your electricity, natural gas, car travel and flights for your estimated annual CO₂e in kilograms, all worked out locally in your browser.
Carbon estimates depend on region, energy mix, fuel type, emission factors, flight distance, and methodology. This is an estimate, not an official inventory. Everything runs locally in your browser and nothing you enter is uploaded.
About this tool
Carbon Footprint is easiest to get wrong in the setup, not the arithmetic. Carbon Footprint Calculator multiplies your electricity, gas, car travel and flights by standard emission factors to estimate annual CO₂e in kilograms. It matters for trips, vehicles and daily decisions where a quick reliable number beats a rough guess. The worked example on this page (Driving 15,000 km/year at ~0.12 kg CO₂ per km emits about 15,000 × 0.12 = 1,800 kg (1.8 t) CO₂/year from the car alone.) shows the full substitution; the calculator above runs the same working on your own numbers, in your browser, with nothing uploaded.
How to use
- Enter your monthly electricity use in kWh.
- Enter monthly natural gas in therms and car travel in km.
- Enter the number of one-way flights per year.
- Press Calculate to see the yearly estimate by source.
Why use the Carbon Footprint Calculator
Instant
Each result is worked out on your device the moment you press Calculate.
Private
The numbers you enter stay in your browser and are never uploaded.
Free
No signup and no paywall to use any tool in this set.
Works offline
Once the page has loaded it keeps working on a weak or dropped connection.
Clear units
Inputs and outputs name their units so you know exactly what you are reading.
Honest by design
Uses simplified browser-side formulas for estimates; emission factors are regional averages that change over time, so treat the total as a guide.
Common uses
Use it when weighing up flights and driving
Use it when comparing year-on-year emissions
Use it when reducing your footprint
Use it for awareness of your emissions
Use it when comparing energy choices
Use it for tracking your household emissions
Technical notes
Carbon Footprint Calculator multiplies your electricity, gas, car travel and flights by standard emission factors to estimate annual CO₂e in kilograms.
Emission factors are regional averages that change over time, so treat the CO₂e figure as a rough estimate.
Because it runs locally, results appear instantly with no server round-trip.
Worked example
Driving 15,000 km/year at ~0.12 kg CO₂ per km emits about 15,000 × 0.12 = 1,800 kg (1.8 t) CO₂/year from the car alone.
FAQ
Which emission factors are used?
The tool uses 0.42 kg CO2e per kWh of electricity, 5.3 kg per therm of gas, 0.21 kg per km driven, and 250 kg per one-way flight. Each factor is shown beside its line in the result.
Are the electricity and car inputs monthly or yearly?
Electricity, gas, and car travel are entered per month and the tool multiplies them by twelve. Flights are entered per year and counted directly.
Is this an official carbon inventory?
No. It is a simplified estimate. Real emissions depend on your region, energy mix, fuel type, flight distance, and the methodology used.
Can I leave some fields blank?
Yes. Any field you leave blank counts as zero, so you can estimate a footprint from just the activities you want to include.