Scope 3 Emissions Calculator Formula

Understand the math behind the scope 3 emissions calculator. Each variable explained with a worked example.

Formulas Used

Total Scope 3 Emissions

total_out = total_scope3

Purchased Goods Share

goods_pct = purchased_goods / total_scope3 * 100

Travel & Commute Share

travel_pct = (business_travel + employee_commuting) / total_scope3 * 100

Waste Share

waste_pct = waste_disposal / total_scope3 * 100

Variables

VariableDescriptionDefault
purchased_goodsPurchased Goods & Services(metric tons CO2e)200
business_travelBusiness Travel(metric tons CO2e)50
employee_commutingEmployee Commuting(metric tons CO2e)80
waste_disposalWaste Disposal(metric tons CO2e)20
total_scope3Derived value= purchased_goods + business_travel + employee_commuting + waste_disposalcalculated

How It Works

How to Calculate Scope 3 Emissions

Scope 3 covers all indirect emissions in your value chain not included in Scope 2. These are typically the largest portion of a company's total footprint.

15 Categories of Scope 3

Upstream: purchased goods/services, capital goods, fuel/energy activities, transportation, waste, business travel, employee commuting, leased assets.

Downstream: product transportation, processing, use of sold products, end-of-life treatment, leased assets, franchises, investments.

Formula

Total Scope 3 = Sum of all category emissions

Worked Example

A mid-size company with estimated Scope 3 across four main categories.

purchased_goods = 200business_travel = 50employee_commuting = 80waste_disposal = 20
  1. 01Purchased goods: 200 metric tons CO2e
  2. 02Business travel: 50 metric tons CO2e
  3. 03Employee commuting: 80 metric tons CO2e
  4. 04Waste disposal: 20 metric tons CO2e
  5. 05Total Scope 3: 200 + 50 + 80 + 20 = 350 metric tons CO2e

Ready to run the numbers?

Open Scope 3 Emissions Calculator