A method of estimating, for a raw sulfur-containing petroleum product, values representative of sulfur and carbon distributions in atmospheric and vacuum distillation residues, and a value representative of the sulfur in the coke, a method wherein the following stages are carried out: - from a sample of some milligrams of said raw sulfur-containing petroleum product, measuring at least parameters S2b, Sulf S2b, RC, Sulf oxy using a device comprising at least one inert atmosphere pyrolysis oven and at least one oxidation oven, said device comprising a sulfur measurement module, S2b being the mass proportion of heavy pyrolyzable compounds contained in said sample, Sulf S2b being the mass proportion of sulfur in the heavy pyrolyzable compounds contained in said sample, RC being the mass proportion of carbon of the pyrolysis residue of said sample, and Sulf oxy being the mass proportion of sulfur in the pyrolysis residue of said sample, - deducing from said measurements of said parameters said values of the sulfur and carbon distributions in the distillation residues, and a sulfur content in relation to the carbon content in the coke, said values representative of sulfur and carbon distributions in atmospheric and vacuum distillation residues being determined as follows: - S PHF = Sulf S2b / [Sulf S2b + Sulf oxy], where S PHF corresponds to the proportion of sulfur in the pyrolyzable heavy fraction, with said parameters Sulf S2b' Sulf S2b and Sulf oxy expressed in gram per gram of said sample, - S COKE = Sulf oxy / [Sulf S2b + Sulf oxy], where S COKE corresponds to the proportion of sulfur in the coke, with said parameters Sulf S2b, Sulf S2b and Sulf oxy expressed in gram per gram of said sample, with S PHF + S COKE = 1, - C PHF = S2b*0.083 / [S2b*0.083 + RC], where C PHF corresponds to the proportion of carbon in the pyrolyzable heavy fraction, with said parameters S2b and RC expressed in gram per gram of said sample, - C COKE = RC / [S2b*0.083 + RC], where C COKE corresponds to the proportion of carbon in the coke, with said parameters S2b and RC expressed in gram per gram of said sample, with C PHF + C COKE = 1; and the value representative of the richness in sulfur in relation to the carbon content in the coke is determined as follows: Sulf oxy /RC, with said parameters Sulfoxy and RC expressed in gram per gram of said sample. - from a sample of some milligrams of said raw sulfur-containing petroleum product, measuring at least parameters S2b, Sulf S2b, RC, Sulf oxy using a device comprising at least one inert atmosphere pyrolysis oven and at least one oxidation oven, said device comprising a sulfur measurement module, S2b being the mass proportion of heavy pyrolyzable compounds contained in said sample, Sulf S2b being the mass proportion of sulfur in the heavy pyrolyzable compounds contained in said sample, RC being the mass proportion of carbon of the pyrolysis residue of said sample, and Sulf oxy being the mass proportion of sulfur in the pyrolysis residue of said sample, - deducing from said measurements of said parameters said values of the sulfur and carbon distributions in the distillation residues, and a sulfur content in relation to the carbon content in the coke, said values representative of sulfur and carbon distributions in atmospheric and vacuum distillation residues being determined as follows: - S PHF = Sulf S2b / [Sulf S2b + Sulf oxy], where S PHF corresponds to the proportion of sulfur in the pyrolyzable heavy fraction, with said parameters Sulf S2b' Sulf S2b and Sulf oxy expressed in gram per gram of said sample, - S COKE = Sulf oxy / [Sulf S2b + Sulf oxy], where S COKE corresponds to the proportion of sulfur in the coke, with said parameters Sulf S2b, Sulf S2b and Sulf oxy expressed in gram per gram of said sample, with S PHF + S COKE = 1, - C PHF = S2b*0.083 / [S2b*0.083 + RC], where C PHF corresponds to the proportion of carbon in the pyrolyzable heavy fraction, with said parameters S2b and RC expressed in gram per gram of said sample, - C COKE = RC / [S2b*0.083 + RC], where C COKE corresponds to the proportion of carbon in the coke, with said parameters S2b and RC expressed in gram per gram of said sample, with C PHF + C COKE = 1; and the value representative of the richness in sulfur in relation to the carbon content in the coke is determined as follows: Sulf oxy /RC, with said parameters Sulfoxy and RC expressed in gram per gram of said sample.