| 646 mm * | 0.0393700787 in | = 25.4330708661 in | 
| 1 mm | 
| Unidad de medida | Longitud | 
|---|---|
| Nanómetro | 646000000.0 nm | 
| Micrómetro | 646000.0 µm | 
| Milímetro | 646.0 mm | 
| Centímetro | 64.6 cm | 
| Pulgada | 25.4330708661 in | 
| Pie | 2.1194225722 ft | 
| Yarda | 0.7064741907 yd | 
| Metro | 0.646 m | 
| Kilómetro | 0.000646 km | 
| Milla | 0.0004014058 mi | 
| Milla náutica | 0.0003488121 nmi | 
