The incline of a treadmill in degrees is not the same as the gradient, which is given in percentage, and some treadmills do not display either figure. Calculate the incline of your treadmill on your own with a measuring tape and a calculator.
Measure the treadmill when flat
Set the treadmill to its flat setting. Use a level or measure the heights of the front and back rollers, which should be equal distances from the floor. Measure the length from roller to roller. This length is the hypotenuse of the triangles you measure later.
Measure the inclined treadmill
Increase the incline of the treadmill. Measure the new distances from the rollers straight down to the ground. The difference between these two heights is the height of the triangle or the rise of the slope.
Use the Pythagorean theorem to solve for gradient
The total length or hypotenuse of the inclined treadmill squared is equal to the sums of the squares of both legs (A? + B? = C?). One of the legs, the height, is already known, as is the hypotenuse (C). Solve for the unknown leg by obtaining the square root of the difference between the hypotenuse squared and the height squared. This second leg can be called the base. Dividing the height by the base and multiplying the product by 100 results in the gradient percentage.
Use trigonometry to solve for incline in degrees
The sine of an angle is equal to the opposite side divided by the hypotenuse. Divide the opposite side (height) by the hypotenuse. Take the inverse sine of the quotient.