This varies a little bit depending on which Mapiful design style you happen to fall in love with! Here are the passepartouts dimensions of the following sizes and styles:
Modern Smooth Legend Pantone Humble Valentine
30x40cm 1.78cm 1.52cm 1.02cm 1.02cm 1.02cm 1.52cm
50x70cm 2.96cm 2.54cm 1.69cm 1.69cm 1.69cm 2.54cm
70x100cm 3.56cm 3.05cm 2.03cm 2.03cm 2.03cm 3.05cm
18x24" 1.05" 0.90" 0.60” 0.60" 0.60" 0.90"
24x36" 1.28" 1.10" 0.73" 0.73" 0.73" 1.10"
11x17" 0.70" 0.60" 0.40" 0.40" 0.40" 1.60"