Liquid organic hydrogen carriers (LOHC) emerged as potential solution for hydrogen storage and transportation for clean fuel technology development in the future. This concept is based on the reversible hydrogenation and dehydrogenation of the LOHC material for hydrogen uptake and release. Recent advancement in LOHC technology proposed the heat-transfer oil dibenzyltoluene (DBT) as a potential LOHC. The reasonable hydrogen storage capacity (6.2-wt%) and thermal stability support its choice for this technology. In order to develop technology based on DBT system, it is important to assess the amount of hydrogen loaded in the carrier. However, DBT is commercially available an isomeric mixture in the market. Reversible hydrogenation and dehydrogenation results in more than 20 intermediate compounds in the reaction mixture. Experimental assessment for the degree of hydrogen loaded in carrier via GC becomes complex and unreliable. In this contribution, various thermophysical properties are correlated to the degree of hydrogenation. Correlations with the degree of hydrogenation, have been evaluated for density, viscosity, refractive index, NMR and Raman spectroscopy. The most reliable correlations were found for density and refractive index. Effectiveness of these properties is further evaluated and correlated for the effect of temperature within range from 10 to 90 ^oC for the estimation of degree of hydrogenation for dibenzyltoluene based systems. The correlations are evaluated for reaction mixtures and found reliable with total standard deviation of 0.10 %.