| 688 cm * | 0.032808399 ft | = 22.5721784777 ft | 
| 1 cm | 
| Natuurkundige eenheid | Lengte | 
|---|---|
| Nanometer | 6880000000.0 nm | 
| Micrometer | 6880000.0 µm | 
| Millimeter | 6880.0 mm | 
| Centimeter | 688.0 cm | 
| Inch | 270.866141733 in | 
| Voet | 22.5721784777 ft | 
| Yard | 7.5240594926 yd | 
| Meter | 6.88 m | 
| Kilometer | 0.00688 km | 
| Mijl | 0.0042750338 mi | 
| Zeemijl | 0.0037149028 nmi | 
