Discloses high purity solvent compositions constituted of n-paraffins and isoparaffins, with the isoparaffins containing predominantly methyl branches, and having an isoparaffin:n-paraffin ratio sufficient to provide superior low temperature properties and low viscosities. The solvent compositions are made by a process wherein a waxy, or long chain paraffinic feed, especially a Fischer-Tropsch wax, is reacted over a dual function catalyst to produce hydroisomerization and hydrocracking reactions at 700.degree. F.+ conversion levels ranging from about 20 to 90 wt. % to provide a C.sub.5 -1050.degree. F. crude fraction. The C.sub.5 -1050.degree. F. crude fraction is then topped via atmospheric distillation to produce a low boiling fraction with an upper end point boiling between about 650.degree. F. and 750.degree. F. The low boiling fraction is fractionated and a narrow boiling range solvent obtained therefrom; one which can be further divided into solvent grades of various boiling ranges.