What is the carbon footprint of a marathon per runner?
Runners' travel to the event is usually the largest share, especially by air. The organiser adds race kits, medals, bottled water, generators and waste. Divide the total by runners. Count travel separately so the organiser can show what it controls.
Organiser controls
- Generators and stage power.
- T-shirts, medals and bibs, by quantity.
- Water bottles and cups.
- Waste collection and disposal.
Runner travel
Estimate from a registration question on city and mode of travel, and report it as a separate figure.
What Senseible does here
Senseible reads bills, fuel invoices and production records into dated, fingerprinted records, so the figure you send a buyer can be traced to its documents.
Sources: GHG Protocol Corporate Value Chain (Scope 3) Standard, ISO, International Organization for Standardization
Last reviewed 2026-10-22.