PIONA (paraffin, isoparaffin, olefin, naphthene, aromatic) is a widely used characterization method for petroleum fractions boiling below 200 ı C, while a gas chromatography-field ionization mass spectrometry (GC-FIMS) characterization method developed at the National Centre for Upgrading Technology (NCUT) provides a reliable hydrocarbon type distribution by carbon number (#C) for middle distillates boiling between 200 ı C-360 ı C. This article proposes an integrated approach to combine the results from both PIONA and GC-FIMS measurements, resulting in detailed hydrocarbon-type distribution between the initial and end boiling points of the middle distillate. Furthermore, summing up the mass in each boiling point (BP) interval (e.g., 10 ı C) generates an equivalent simulated distillation (SimDis) curve that needs to be reconciled with the SimDis measured by the ASTM D2887 method. This article also discusses a simple data reconciliation approach that allowed us to use the three separate pieces of information (PIONA, GC-FIMS, and SimDis) as an internally consistent basis for the derivation of molecular representation of materials characterized in such a way.