Mph stands for miles per hour while km/h stands for kilometers per hour. They are both ways of measuring how fast something is going, but mph is used in the United States while km/h is used in most other countries. One mph is equal to 1.609 kilometers per hour (km/h). This means that to convert from mph to km/h, you just need to multiply by 1.609. For example, 60 mph would be 96.5 km/h. To convert from km/h to mph, you would divide by 1.609. So, 80 km/h would be 49.7 mph.