Treadmills delivered in the United States are usually set to display your speed in miles per hour -- but factory errors are possible. Switching your treadmill from kph to mph is usually as simple as pushing a button; it's finding the right button that's the trick.
Precor and Life Fitness
The sequence of buttons for changing your treadmill's readout varies enormously between brands. For example, on the Precor 9.1 and 9.2s, you turn the treadmill on, then when prompted to enter your weight you hold both the "Speed Up" and "Scan" keys to bring up the kph/mph prompt. For the Life Fitness T3 treadmill, access the user menu by turning the treadmill on while holding the Enter key. Use the Up or Down buttons to access the "Units" option, then press the Time Arrow keys until distance units are displayed.
Spirit Fitness and NordicTrack
For the Spirit Fitness CT800 treadmill, insert the safety key while holding down the Start, Stop and Enter keys. Once "Engineering Mode Menu" shows on the display, release the keys and press the Enter button. Use the Up arrow to scroll through the settings to Functions, press Enter, then use the Up arrow to scroll to "Units"; press Enter to bring up the mph/kph prompt. On the NordicTrack Commercial 1750, insert the key and select the Start menu on the touch screen. Press the "i," then touch the US/Metric button on the screen to access the unit of measurement.