How wide does your ventilation hood need to be?

For kitchens of small or medium size
Ventilation hoods in widths of 24" (60 cm), 30" (75 cm), and 32" (80 cm).
For large and open kitchens
Ventilation hoods in 36" (90 cm), 44" (110 cm), and 48" (120 cm).
Features depend on model