Bilan Carbone® and the GHG Protocol measure the same emissions from the same data. Bilan Carbone® is the French standard (BEGES, ADEME, Diag Décarbon'Action), whereas the GHG Protocol is the international standard (CSRD, CDP and the Science Based Targets initiative, SBTi). A good service provider produces both formats. The detailed comparison is in our dedicated article.
Read the source article: Bilan Carbone® method: what it measures and how to run one