Carbon footprint calculator

Estimate fuel-combustion and purchased-electricity CO2 for a period from consumption and an entered electricity factor.

On your device · No account

Privacy details

Carbon footprint calculator processes your input in this browser. Inputs and results are excluded from analytics. Recent tools save tool names, visit counts and last-visit times. Saved tools store only their names. Draft saving is optional and stays on this device; delete saved text with the draft controls. Loading text from a URL is optional and contacts that server; its URL and your IP address are visible to the server. An optional “Use in” action keeps a handoff in this tab. The next tool removes it on arrival and ignores it if more than a minute has passed.

Copy link includes the inputs you choose to share in the address. Anyone with that link can reopen them. Files and generated results are excluded. Password and key tools share settings only.

Gasoline consumed in period (US gallons)

Diesel consumed in period (US gallons)

More inputs and assumptions

Electricity consumed in same period (kWh)

Your electricity CO2 factor (kg / kWh)

Answer

…

Estimate fuel-combustion and purchased-electricity CO2 for a period from consumption and an entered electricity factor.

More results

Precision and calculation record

Decimal places in numeric results and text downloads

Rounding changes displayed numbers, not the calculation. Text, fractions, matrices and CSV schedules keep their own formatting. Automatic keeps up to 12 significant digits, with money shown to cents where applicable.

Saved scenario

Save the current answer, then change an input to compare. This clears when you leave.

Formula and assumptions

Fuel factors are EPA tailpipe CO2 values: gasoline 8.887 and diesel 10.180 kg per US gallon. Enter an electricity CO2 factor for your supplier or region and reporting year; 0.4 is an editable example, not a national default. Results cover only these entered energy sources, not a complete personal footprint, CO2-equivalent inventory, upstream fuel production, food, flights or embodied emissions. Keep all quantities in the same period.

Automatic precision shows numbers to 12 significant digits. Thousands separators such as 1,000 are accepted; use a dot for decimals.

Scratch calculator

Check another calculation

Use +, −, ×, ÷, parentheses and %. A percentage is divided by 100. This does not change the main tool.

Reset reloads the tool with its starting values and releases open files and device controls. Saved drafts stay on this device until you delete them.

Links include your inputs and settings. Anyone with the link can see them, so leave out private text. Files and generated results are left out; random draws run again.

Keyboard shortcuts

Updated 2026-09-29

Using Carbon footprint calculator

Estimate fuel-combustion and purchased-electricity CO2 for a period from consumption and an entered electricity factor.

Next: Electric vehicle fuel savings calculator

Next: Electricity cost calculator

A worked example

For gasoline consumed in period (us gallons) = 100, diesel consumed in period (us gallons) = 0, electricity consumed in same period (kwh) = 1000, your electricity co2 factor (kg / kwh) = 0.4, selected energy co2 (kg) = 1288.7.

Before you use the result

Example results for gasoline consumed in period (us gallons)

These examples use Diesel consumed in period (US gallons): 0; Electricity consumed in same period (kWh): 1000; Your electricity CO2 factor (kg / kWh): 0.4. They are reference calculations, not recommended settings.

Gasoline consumed in period (US gallons)	Selected energy CO2 (kg)
50	844.35
100	1288.7
200	2177.4

Cite this page

Citation style

ToolOctopus. “Carbon footprint calculator.” Updated 2026-09-29. https://tooloctopus.com/carbon-footprint-calculator.

Add an access date if your instructions require one.

Citation formatting uses citeproc-js by Frank Bennett and Citation Style Language styles. Licence and source code.