The total AC losses of YBCO conductors (Y-Cs) and a BSCCO multifilamentary tape (Bi-MT) that have the same engineering current densities and carry an AC transport current in an AC transverse magnetic field with various orientations were compared based on experimental results. The measurements were carried out by using a 3.9 mm wide Bi-MT and 10 mm wide YBCO film fabricated on sapphire simulating a Y-C. If we assume that this YBCO film is fabricated on a metal substrate and that the total thickness of the assumed Y-C is 0.11 mm, the engineering current densities of the assumed Y-C and the Bi-MT are almost the same. Based on the fact that the total AC loss of Y-Cs that carry AC transport current in an AC transverse magnetic field with various orientations is proportional to the width of the Y-Cs, the total AC loss of the Y-C whose width is the same as that of the Bi-MT was estimated from the measured data of the 10 mm wide Y-C. The total AC losses of the 10 mm wide and 3.9 mm wide Y-Cs were compared with those of the Bi-MT in transverse magnetic fields with various orientations.