Quick answer
Travel emissions = distance × emission factor. 1,500 km at 0.255 kg CO₂ per km emits 382.5 kg of CO₂, or 0.3825 metric tons.
Enter the distance and the emission factor. The calculator returns the CO₂ in kg and metric tons.
Related tools: Fuel Emissions Calculator: CO₂ from burning gasoline or diesel. Electricity Emissions Calculator: CO₂ from electricity use at an emission factor you enter. Greenhouse Gas Conversion Calculator: Convert methane or nitrous oxide to CO₂ equivalent (100-year GWP).
How to use the Travel Emissions Calculator
- Enter distance traveled (km) (above 0).
- Enter emission factor (kg CO₂/km) (above 0).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Distance traveled | A number, in km | > 0 |
| Emission factor | A number, in kg CO₂/km. Per vehicle or per passenger, from a published source | > 0 |
Formula and method
Formula
CO₂ = distance × emission factor
IEEE-754 double precision; shown to the decimals indicated.
Emission factors depend on vehicle, occupancy and fuel, so enter one from a published source.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Distance traveled = 1500; Emission factor = 0.255.
| Result | Value |
|---|---|
| CO₂ emitted | 382.5 kg CO₂ |
| Metric tons | 0.3825 |
Example 2
Inputs: Distance traveled = 40; Emission factor = 0.171.
| Result | Value |
|---|---|
| CO₂ emitted | 6.84 kg CO₂ |
| Metric tons | 0.0068 |
Example 3
Inputs: Distance traveled = 12000; Emission factor = 0.09.
| Result | Value |
|---|---|
| CO₂ emitted | 1,080 kg CO₂ |
| Metric tons | 1.08 |
The first line is the headline result (cO₂ emitted). Below it the travel Emissions Calculator lists metric tons, which describe the same case from other angles. IEEE-754 double precision; shown to the decimals indicated.
Choosing a factor
The factor is vehicle-specific: a petrol car is about 0.17 to 0.25 kg/km, a train 0.03 to 0.05 per passenger-km, a short-haul flight about 0.15 to 0.25 per passenger-km. Use factors for your mode and country.
Per passenger
For a shared vehicle divide by the number of occupants. At 0.255 kg/km with 3 people, each emits 85 g per km. Include the distance both ways for round trips.
How the result changes with distance traveled
Holding every other input at the first worked example, this table changes only distance traveled. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Distance traveled | CO₂ emitted | Metric tons |
|---|---|---|
| 750 | 191.25 kg CO₂ | 0.1913 |
| 1500 | 382.5 kg CO₂ | 0.3825 |
| 3000 | 765 kg CO₂ | 0.765 |
| 6000 | 1,530 kg CO₂ | 1.53 |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Distance traveled: entering "0" shows "Distance traveled must be greater than 0." beside that field and no result.
- Emission factor: entering "0" shows "Emission factor must be greater than 0." beside that field and no result.
Choosing between the Travel Emissions Calculator and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Fuel Emissions Calculator](/science/fuel-emissions-calculator/) | fuel and fuel burned | CO₂ emitted |
| [Electricity Emissions Calculator](/science/electricity-emissions-calculator/) | electricity used and emission factor | CO₂ emitted |
| [Greenhouse Gas Conversion Calculator](/science/greenhouse-gas-conversion-calculator/) | gas and mass emitted | CO₂ equivalent |
| [Travel Budget Calculator](/lifestyle/travel-budget-calculator/) | trip length, lodging per night and food per day | Total trip cost |
| [Carbon Footprint Estimate Calculator](/science/carbon-footprint-estimate-calculator/) | miles driven per year, electricity used per year and natural gas used per year | Estimated emissions |
Background: environment and acoustics
Decibels are a logarithmic scale, so sound levels cannot be added arithmetically: two equal sources raise the level by about 3 dB, not double it. Environmental and emissions results depend on the factors behind them (for example the US EPA's equivalency factors), which are averages for a country, fuel and year.
Use the result to compare scenarios rather than as a measured value.
Assumptions and limitations
- Factor is vehicle-specific
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for distance traveled and emission factor to confirm this.
Frequently asked questions
Which mode has the lowest emissions?
Walking, cycling and electric rail.
Do flights include contrails?
Not unless the factor does.
Where do I find factors?
In government emission-factor tables.
What does the Travel Emissions Calculator calculate?
CO₂ from a trip at an emission factor you enter. It returns CO₂ emitted and Metric tons.
What formula does the Travel Emissions Calculator use?
CO₂ = distance × emission factor. Emission factors depend on vehicle, occupancy and fuel, so enter one from a published source.
What do I need to enter in the travel Emissions Calculator?
You enter Distance traveled (km) and Emission factor (kg CO₂/km).
How is the result rounded or limited?
IEEE-754 double precision; shown to the decimals indicated. Factor is vehicle-specific.
What is an example of a travel Emissions result?
With distance traveled 1500 and emission factor 0.255, the cO₂ emitted is 382.5 kg CO₂.
Where does the method come from?
The method follows: Published transport emission factors (e.g. UK DESNZ conversion factors; US EPA).
Related calculators
- Fuel Emissions Calculator — CO₂ from burning gasoline or diesel.
- Electricity Emissions Calculator — CO₂ from electricity use at an emission factor you enter.
- Greenhouse Gas Conversion Calculator — Convert methane or nitrous oxide to CO₂ equivalent (100-year GWP).
- Travel Budget Calculator — Total trip cost from daily and one-off costs.
- Carbon Footprint Estimate Calculator — Annual greenhouse-gas emissions from driving, home electricity and natural gas using US EPA emission factors.
- Tree Carbon Uptake Estimate Calculator — Carbon dioxide removed by planted tree seedlings and by forest land, using US EPA factors.
Sources
- Published transport emission factors (e.g. UK DESNZ conversion factors; US EPA)
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.