Calculator inputs
Enter your operational activity data, then submit.
Formula used
This estimator applies activity data multiplied by emission factors.
- Scope 1 (kg) = Σ(fuel units × factor) + Σ(refrigerant kg × GWP factor)
- Scope 2 location (kg) = electricity kWh × grid factor
- Scope 2 market (kg) = (kWh − renewable kWh) × grid factor
- Scope 3 (kg) = Σ(distance × factor) + Σ(waste × factor) + water × factor + spend/1000 × spend factor
- Gross (t) = (Scope1 + Scope2 + Scope3) / 1000
- Net (t) = max(Gross − offsets, 0)
- tCO₂e per employee = Net t / employees
- tCO₂e per revenue = Net t / revenue (million)
How to use this calculator
- Collect activity data for the same reporting period.
- Select a region grid factor, or set a custom one.
- Enter Scope 1 fuels and refrigerant leakage estimates.
- Enter electricity use and any renewable portion.
- Fill Scope 3 categories you can measure reliably.
- Enter offsets or removals only if verified.
- Press submit to view totals and intensity metrics.
- Download CSV or PDF for sharing and archiving.
Example data table
Sample values illustrate how a footprint can be decomposed by scope.
| Scenario | Scope 1 (tCO₂e) | Scope 2 (tCO₂e) | Scope 3 (tCO₂e) | Offsets (tCO₂e) | Net (tCO₂e) |
|---|---|---|---|---|---|
| Baseline operations | 18.6 | 93.6 | 146.2 | 0.0 | 258.4 |
| Efficiency + renewables | 16.1 | 62.4 | 140.0 | 0.0 | 218.5 |
| With verified removals | 16.1 | 62.4 | 140.0 | 50.0 | 168.5 |
Operational insights
Define boundaries and reporting period
Start by setting organizational boundaries (equity share or control) and a clear reporting period. Align facilities, fleets, and purchased energy to the same months. This calculator supports activity inputs that can be rolled up across sites, then compared year over year using net tCO₂e, tCO₂e per employee, and tCO₂e per revenue.
Separate Scope 1, Scope 2, and Scope 3 drivers
The tool estimates Scope 1 from fuels and refrigerant leakage, Scope 2 from electricity, and selected Scope 3 categories such as travel, commuting, waste, water, and spend. A scope split helps you locate hotspots: high fuel litres suggest fleet efficiency actions, while high kWh points to building performance, equipment tuning, and load management.
Use grid factors and renewables consistently
Electricity emissions depend on the grid factor (kgCO₂e/kWh). Choose a regional factor or enter a custom value that matches your inventory source. For market-based estimates, the renewable kWh field reduces the chargeable kWh. Keep certificates and procurement evidence ready so any renewable adjustment is auditable and traceable.
Improve data quality with measurable activity data
Accuracy improves when inputs come from invoices, meters, fuel cards, travel systems, and waste tickets. If you must estimate, document assumptions and apply them consistently. Treat spend-based Scope 3 as a screening approach, then replace it with supplier factors or product data for material categories to reduce uncertainty.
Translate results into targets and action plans
Use gross versus net results to discuss offsets responsibly. Prioritize reductions first: cut kWh through efficiency, reduce travel kilometres by switching to rail or virtual meetings, and divert waste from landfill. Track intensity metrics to normalize growth, and set targets like a 10–20% reduction over 12 months, supported by monthly monitoring.
FAQs
1) What does this calculator estimate?
It estimates organizational greenhouse gas emissions using activity data across Scope 1 fuels and refrigerants, Scope 2 electricity, and selected Scope 3 categories. It also reports net totals after offsets and shows intensity metrics for benchmarking.
2) Why are there two Scope 2 totals?
Location-based uses the full kWh multiplied by a grid factor. Market-based subtracts renewable kWh before applying the same grid factor. Use market-based only when renewable claims are supported by documented procurement evidence.
3) Can I change emission factors?
Yes. The tool includes editable fields for grid factor and spend factor. For compliance reporting, replace default factors with your approved dataset and document the source, vintage year, geography, and any conversion assumptions.
4) How should I treat spend-based Scope 3?
Spend factors provide a fast screening estimate when supplier data is missing. Use them to identify priority categories, then transition to supplier-specific or product-based factors for high-impact purchasing to reduce uncertainty.
5) What are the CSV and PDF exports for?
Exports capture the inputs and calculated results for sharing, audits, and internal reviews. CSV supports analysis and dashboards, while PDF provides a lightweight snapshot for approvals, ESG packs, and project documentation.
6) Is this suitable for official disclosures?
It is an estimator for planning and internal insight. For official disclosures, apply your formal boundary rules, verified factor sources, and complete Scope 3 category coverage. Validate results through governance and assurance processes.