Azimuthally averaged radial profiles of the three CO isotopologues in all 23 Herbig disks in which at least one isotopologue is detected. The 1σ uncertainty interval is indicated by the shaded region in the same color as the profile. The vertical solid lines indicate the derived 90% radii for each line. An upper limit on the radius is indicated with a left facing arrow. The beam size is illustrated by the horizontal lines in the top right of each panel.