Using a life-cycle approach, we estimated the CO₂ process emission and uptake of cement materials produced and consumed from 1930 to 2019; ~21 Gt of CO₂, about 55 % of the total process emission, had been abated through cement carbonation. China contributed the greatest to the cumulative uptake, with more than 6 Gt (~30 % of the world total), while ~59 %, or more than 12 Gt, of the total uptake was attributed to mortar. Cement CO₂ uptake makes up a considerable part of the human carbon budget.