As an Earthling, it's easy to believe that we're standing still. After all, we don't feel any movement in our surroundings. But when you look at the sky, you can see evidence that we are moving.
Earth's spin is constant, but the speed depends on what latitude you are located at. The circumference is roughly 24,898 miles (40,070 kilometers) at the equator, according to NASA. If you estimate that a day is 24 hours long, you divide the circumference by the length of the day. This produces a speed at the equator of about 1,037 mph (1,670 km/h).