Calculator inputs
Use the responsive field grid below. It shows three columns on large screens, two on smaller screens, and one on mobile.
Example data table
| Input or output | Example value | Notes |
|---|---|---|
| Reporting period | Monthly | Annualized by multiplying monthly totals by 12. |
| Electricity use | 12,000 kWh | 10% renewable share, factor 0.42 kg CO2e/kWh. |
| Natural gas | 500 therms | Factor 5.30 kg CO2e/therm. |
| Diesel and petrol | 250 L and 180 L | Direct fuel emissions under Scope 1. |
| Travel | 3,200 km air, 1,800 km car | Both are tracked under Scope 3 here. |
| Waste and water | 900 kg and 140 m³ | Use editable operational factors. |
| Refrigerant leakage | 2 kg at GWP 1430 | High impact source with direct effect. |
| Gross monthly total | 12.514 t CO2e | Total before annualization and offsets. |
| Net annual total | 142.173 t CO2e | After applying 8.000 t annual offsets. |
Formula used
Source emissions: Emissions for each source equal activity data multiplied by its emission factor.
Electricity adjustment: Adjusted electricity equals electricity use multiplied by one minus renewable share.
Scope totals: Each scope total equals the sum of sources assigned to that scope.
Annualized gross total: Gross period total multiplied by the selected period multiplier.
Net annual total: Annualized gross total minus annual offsets, never below zero.
Intensity metrics: Net annual total divided by employees, revenue basis, or floor area.
How to use this calculator
Enter your organization name and select the reporting period.
Fill in activity data for electricity, fuels, travel, waste, water, and refrigerant leakage.
Update the emission factors to reflect your preferred inventory method or local guidance.
Add employees, revenue, floor area, and any annual offsets for intensity analysis.
Click the calculate button to view totals, scope splits, source breakdown, and the graph.
Use the export buttons in the result section to download CSV or PDF output.
FAQs
1. What does this calculator measure?
It estimates carbon output from common operational sources such as electricity, fuels, travel, waste, water, and refrigerant leakage. Results are grouped into Scope 1, Scope 2, and Scope 3 totals.
2. Why are emission factors editable?
Different countries, utilities, and reporting frameworks use different factors. Editable inputs let you align the calculator with internal sustainability rules, consultant advice, or local regulatory reporting methods.
3. How is renewable electricity handled?
The calculator reduces electricity activity by the renewable percentage before multiplying by the electricity factor. This gives you a quick adjusted grid-based estimate for the selected reporting period.
4. What are the scope totals?
Scope 1 covers direct fuel and refrigerant emissions, Scope 2 covers purchased electricity, and Scope 3 covers selected indirect items such as travel, waste, and water.
5. How are annual totals calculated?
The calculator multiplies the selected period total by an annualization factor. Monthly results use 12, quarterly use 4, semiannual use 2, and annual results use 1.
6. What do the intensity metrics show?
They show net annual emissions relative to staffing, revenue, and floor area. These ratios help compare sites, track efficiency, and support planning even when business size changes.
7. When should I use the export buttons?
Use them after calculating results. The CSV file supports spreadsheet analysis, while the PDF file provides a quick summary document for reporting packs, reviews, or internal sharing.
8. Can this replace a full verified inventory?
No. It is a practical planning and screening tool. For assurance, disclosure, or audited reporting, confirm boundaries, factors, scopes, and methodology with qualified sustainability guidance.