The yield and properties of char derived from the co-digested manure and its main macro-components, including organic (cellulose, lignin, and protein) components and an inorganic component (CaCO3), produced at different pyrolysis temperatures (350, 550, and 750 °C) have been studied. Experimental results obtained from a surrogate co-digested manure were compared with the theoretically calculated values to explore potential interactions between these macro-components. The char properties analyzed included elemental analysis, pH, FTIR, XPS, and specific surface area. The effect of pyrolysis temperature on many properties was similar, regardless of the precursor (macro-component). Increasing pyrolysis temperature led to higher C content (>90 wt% for cellulose char at 750 °C), pH (from (∼7 for cellulose at 350 °C to ∼13 for co-digested manure), and specific surface area, observing a marked development of ultramicroporosity and microporosity, especially at the highest pyrolysis temperature studied, 750 °C. An exception was observed for the char derived from proteins due to melting during pyrolysis. By far, the solids from the pyrolysis of cellulose and lignin exhibited the most microporosity development (SSDR ≥ 650 m2 g-1), reaching, at the highest temperature studied, values close to those of physically activated carbons. Pyrolysis of the surrogate co-digested manure revealed the occurrence of Maillard reactions and also showed an interesting interaction involving CaCO3. The CaCO3 thermal decomposition is promoted when it is embedded into the organic matrix, where the CO2 generated during decomposition favored the Boudouard reaction of C from the organic components. This results in a lower biochar yield, 32 wt% versus 37 wt% (expected value), and a higher development of microporosity in the char.