Fluoroantimonic acid (HF:SbF5, H0 between −21 and −23) Magic acid (HSO3F:SbF5, H0 = −19.2) Triflidic acid (CH(CF3SO2)3, H0 = −18.6) Carborane acids (H(HCB11X11), H0 ≤ −18, indirectly determined and depends on substituents) Fluoroboric acid (HF:BF3, H0 = −16.6) Fluorosulfuric acid (FSO3H, H0 = −15.1) Hydrogen fluoride (HF, H0 = −15.1) Triflic acid (HOSO2CF3, H0 = −14.9) Perchloric acid (HClO4, H0 = −13) Sulfuric acid (H2SO4, H0 = −11.9) See also Superbase Acid dissociation constant References