Imperial measurements are often based on the human body: an inch is the width of a thumb, a yard is the distance between your nose and your outstretched finger, a fathom is outstretched finger to outstretched finger, a mile is a thousand paces, hands are still used to measure horses...
This is great for estimation, but these separate measurements had to be massaged to get them all on the same base (there were three different definitions of the fathom in use well into the 1700s) so the result is somewhat arbitrary (4 inches to a hand, 3 hands to a foot, 6 feet to a fathom, 880 fathoms to a mile). Metric's clearly the more consistent, simpler system for anything beyond estimates.
The closest to what you're looking for is probably the decimetre (dm) at 100mm (roughly one hand). But in everyday speech, "30 centimetres" sounds less clunky than "3 decimetres", and in technical speech everything human-scale is done in mm.
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Imperial measurements are often based on the human body: an inch is the width of a thumb, a yard is the distance between your nose and your outstretched finger, a fathom is outstretched finger to outstretched finger, a mile is a thousand paces, hands are still used to measure horses...
This is great for estimation, but these separate measurements had to be massaged to get them all on the same base (there were three different definitions of the fathom in use well into the 1700s) so the result is somewhat arbitrary (4 inches to a hand, 3 hands to a foot, 6 feet to a fathom, 880 fathoms to a mile). Metric's clearly the more consistent, simpler system for anything beyond estimates.
The closest to what you're looking for is probably the decimetre (dm) at 100mm (roughly one hand). But in everyday speech, "30 centimetres" sounds less clunky than "3 decimetres", and in technical speech everything human-scale is done in mm.