| 8.1 mm * | 0.1 cm | = 0.81 cm | 
| 1 mm | 
| Units of measurement | Length | 
|---|---|
| Nanometre | 8100000.0 nm | 
| Micrometre | 8100.0 µm | 
| Millimetre | 8.1 mm | 
| Centimetre | 0.81 cm | 
| Inch | 0.3188976378 in | 
| Foot | 0.0265748031 ft | 
| Yard | 0.0088582677 yd | 
| Metre | 0.0081 m | 
| Kilometre | 8.1e-06 km | 
| Mile | 5.0331e-06 mi | 
| Nautical mile | 4.3737e-06 nmi | 
