The two frameworks are often named in the same breath, but they do different jobs. GHG Protocol is an accounting methodology; ISO 14064 is a verification standard. Using one in place of the other leaves your inventory needlessly fragile.
GHG Protocol tells you how to build the inventory: how to draw organisational boundaries, how to divide emissions into scopes, which gases to include. It is practical, detailed, and the most widely used corporate accounting framework in the world.
ISO 14064-1, by contrast, defines for whom and how your inventory can be verified. It standardises what an auditor will check, which documents must be retained, and which uncertainty statements must be made. In short: you calculate with GHG Protocol, you prove with ISO 14064.
Most mature inventories use both: built on GHG Protocol methodology, verified against ISO 14064. Rather than viewing the two frameworks as rivals, think of them as a division of labour.
— Ayşe, May 2026