I was building GreenCalculus (carbon accounting/calculator platform — disclosure: it’s my project) and kept running into the same problem: There’s no single clean, open, version-controlled emission factor dataset aligned to IPCC AR6 GWP-100. The data exists, but it’s scattered across: DEFRA EPA IEA IPCC PDFs …with different units, different GWP vintages, and almost no visibility into what changed between versions. So I consolidated it into one open repo: https://github.com/greencalculus/greencalculus-methodology Everything is free, public, and downloadable. No signup, no API key. What’s inside: gwp-values.json AR6 + AR5 values side-by-side for 16 greenhouse gases. emission-factors.json + .csv Scope 1 fuel combustion + Scope 2 electricity grid factors across 15 countries. METHODOLOGY.md Full calculation methodology with formulas + source references. CITATION.cff Makes it easy to cite in BibTeX / APA.…