Free Emission Reduction calculator with clear step-by-step results.
A reduction claim needs two numbers, not one: a baseline and a current figure. The absolute reduction is the difference, and the percentage is that difference over the baseline. Intensity tells a different and equally important story — emissions per unit of output can fall while absolute emissions rise if the business grows, which is why science-based targets are set on absolute emissions and intensity is reported alongside rather than instead.
Absolute and relative
Reduction = baseline − current; % reduction = reduction ÷ baseline × 100
Intensity
Intensity = emissions ÷ output; intensity reduction % = (baseline intensity − current intensity) ÷ baseline intensity × 100
Emissions accounting, baseline recalculation and target-setting follow prescribed protocols such as the GHG Protocol and SBTi criteria. Reported or assured figures require the applicable methodology and, usually, third-party verification.
The atmosphere responds to absolute tonnes, so that is the figure targets are set against. Intensity is useful for showing operational improvement and for comparing sites of different sizes, but growth can hide a rising absolute total behind a falling intensity.
A representative recent year with complete, verifiable data — not an unusually high one. Recalculate the baseline after acquisitions, divestments or methodology changes so the comparison stays like for like.
Not in this calculation, and not under most reporting standards. Purchased offsets are reported separately from gross reductions in your own operations and value chain.