MPH to KM/H Calculator

The conversion factor between miles per hour and kilometers per hour is identical to the factor between miles and kilometers, because both speed units measure distance covered in one hour. One international mile is defined as exactly 1.609344 kilometers, so one mile per hour equals exactly 1.609344 kilometers per hour. The calculator multiplies the mph input by 1.60934, a rounded form of this exact value that retains accuracy to five significant figures. The result is displayed to four decimal places for precision. For reference, 60 mph × 1.60934 ≈ 96.5604 km/h, 65 mph is approximately 104.61 km/h, and 100 mph equals 160.934 km/h. A common mental approximation is to multiply mph by 1.6, but using 1.60934 gives a more accurate result, particularly important when comparing speeds near regulatory limits or performance benchmarks.