Results
Footprint and intensity
- Total emissions
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- Scope 1
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- Scope 2
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- Scope 3
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- Intensity
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- After planned changes
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Calculator Library / Sustainability
Carbon Footprint and Intensity Calculator
Turn energy and fuel data into emissions by scope, see which sources matter most, calculate intensity, and test the effect of planned reductions.
Tool
List your emission sources, activity data, and factors
Emissions = activity × emission factor
| Source | Scope | Annual activity | Unit | Factor (kg CO2e per unit) | Planned change (%) | Emissions (t CO2e) |
|---|
The example factors are illustrative and simplified to carbon dioxide. Use current factors for your region and year from an authoritative source, such as a national inventory or your energy supplier. Data saves in this browser only and nothing is sent to a server.
Sources
Emissions by source
Instructions
How to use this app
- Define your boundary first: which sites and which scopes you are counting, and keep it the same between years.
- For each source, enter the activity from bills and meters, its unit, and the emission factor you are using, and choose the scope.
- Enter the annual output to see intensity, so changes in volume do not hide efficiency.
- Enter planned changes as a percent of each source's activity to see the effect on the total.
- Record the baseline year, the factors, and their sources so results can be repeated and explained.
What This Carbon Footprint and Intensity Calculator Helps You Decide
This calculator turns activity data, such as kilowatt-hours, therms, and gallons, into emissions using emission factors you supply. It totals them by scope, calculates intensity per unit of output, and shows the effect of planned reductions.
Use it to see which sources dominate, to set a baseline, and to test whether planned changes are large enough to matter before you invest in them.
How It Works
| Measure | Rule | Meaning |
|---|---|---|
| Emissions | Activity × emission factor ÷ 1,000 | Tonnes of CO2e for each source, when the factor is in kg per unit. |
| Scope totals | Sum of sources tagged Scope 1, 2, or 3 | Direct, purchased-energy, and value-chain emissions. |
| Intensity | Total emissions ÷ output | Kilograms of CO2e per thousand units of output. |
| After planned changes | Sum of emissions × (1 + change %) | The projected total if every change is made. |
Worked Example: A Facility Baseline
The pre-loaded example has electricity (900,000 kWh at 0.40 kg per kWh, Scope 2), natural gas (30,000 therms at 5.3 kg per therm, Scope 1), and fleet diesel (12,000 gallons at 10.2 kg per gallon, Scope 1). Total emissions are 641.4 tonnes: 360.0 from electricity, 159.0 from gas, and 122.4 from diesel, with Scope 1 at 281.4 and Scope 2 at 360.0. With 4,200 thousand units of output, intensity is 152.7 kilograms per thousand units.
The planned changes are minus 6% for electricity (leak repair), minus 6% for gas (boiler tuning), and minus 7.5% for diesel (routing). Together they cut 40.3 tonnes, about 6.3% of the total, to 601.1 tonnes.
Limits and Good Practice
- The example factors are illustrative and simplified to CO2 only. Real reporting should use current, documented factors for your region and year, and include other greenhouse gases where required.
- Scope 2 has location-based and market-based methods. Choose one, state it, and apply it consistently.
- This calculator does not replace a recognized reporting standard, assurance, or legal advice. Check any regulatory or customer reporting requirements that apply to you.
- Data stays in your browser and is saved locally. Use Clear all to remove it.
Carbon Footprint and Intensity Calculator Frequently Asked Questions
How is carbon footprint calculated here?
For each source the calculator multiplies annual activity, such as kilowatt-hours or gallons, by the emission factor you enter in kilograms of CO2e per unit and divides by 1,000 to give tonnes. Sources are totaled by scope, and intensity is total emissions divided by output.
Where do I get emission factors?
Use current factors for your region and year from an authoritative source, such as a national greenhouse gas inventory, your electricity supplier or utility, or a recognized database. The pre-loaded factors are illustrative only, and you should record which factors you used and where they came from.
What are Scope 1, 2, and 3?
Scope 1 is direct emissions from sources you own or control, such as boilers and company vehicles. Scope 2 is indirect emissions from purchased electricity, steam, heat, or cooling. Scope 3 covers other indirect emissions in the value chain, such as purchased goods, shipping, and product use.
Is my data stored anywhere?
No. The calculator runs in your browser and saves your entries only in your browser's local storage. Nothing is sent to a server, and Clear all removes the entries.