Avgas 100LL CO₂ emissions per gallon and liter

Avgas 100LL to CO₂ converter

Enter the fuel you burned. The result is the CO₂ from burning it, and what it costs to offset.

CO₂ from common amounts of avgas 100LL

Our factor next to the agencies' factors

Each agency publishes its own figure for this fuel. They differ because of the fuel density and heat content each one assumes.

Each agency publishes one unit. We convert volumes at 3.785 liters per US gallon, and show a per-kg figure only where the agency gives one. CO₂e adds methane and nitrous oxide to CO₂. The per-kg figure on this page uses 0.73 kg per liter.

Where the number comes from

The US EPA gives this fuel 69.25 kg of CO₂ per million BTU and 0.120 million BTU per US gallon. Multiplied together, that is 8.31 kg per gallon. Divide by 3.785 liters per gallon for the per-liter figure of 2.20 kg.

Unleaded avgas: UL91, UL94, G100UL and 100R

We found no CO₂ factor for any unleaded avgas grade from the US EPA, UK DESNZ, France's ADEME or ICAO. These grades are petroleum fuels close to 100LL in composition, so this page's factor applies to them too. Treat the result as an estimate until producers publish their own figures.

What each unleaded grade changes for CO₂

What this factor covers

The factor covers burning the fuel only: the CO₂ that leaves the exhaust. It leaves out producing, refining and moving the fuel, and effects other than CO₂ such as contrails.

Counting the whole chain (well to wake) gives a higher figure. UK DESNZ lists 0.61 kg of CO₂e per liter to produce and deliver this fuel, which is 27% on top of the 2.28 kg of CO₂ per liter from burning it. We do not add it to your figure: one basis keeps every aircraft page comparable.

Aircraft on TrimCarbon that burn avgas 100LL

CO₂ per flight hour at typical cruise fuel flow. Each name links to the aircraft's own page.

Worked examples

• A 2-hour flight in a Cessna 172 Skyhawk burns 21.2 US gal (80 L) of avgas 100LL. At 8.31 kg per gallon, that is about 176 kg of CO₂.
• Burning 100 L of avgas 100LL releases about 220 kg of CO₂, or 0.22 tonnes. That fuel is 26.4 US gal and weighs about 73 kg.

Keep reading

• GuideHow to calculate your flight's CO₂ emissionsThe formula, the emission factors for avgas and jet fuel, three ways to get your fuel figure, and a worked example for a year of flying a Cessna 172.
• GuideUnleaded avgas fixes lead, not CO₂: what each new fuel changes for your planeUnleaded avgas barely moves your CO₂ per hour. By Diamond's figures, a Jet-A diesel DA40 cuts it by about 15% to 27%. What each new fuel changes, with a checklist for owners, renters, schools and clubs.
• CalculatorFlight emissions calculatorEstimate the CO₂ of a year of flying in your aircraft.
• FuelMogas8.78 kg of CO₂ per US gallon and 2.32 kg per liter.
• FuelJet A and Jet A-19.75 kg of CO₂ per US gallon and 2.58 kg per liter.
• FuelAll fuelsAvgas 100LL, mogas and Jet A side by side, per gallon and per liter.