V belts are NOT measured by diameter nor folding the belt in half. The most accurate way to measure the circumference of a belt is with a v belt measuring tool or using a cloth tape measure (Not a steel tape measure or ruler). An additional option is to wrap a small diameter string/rope around the belt, then measure the length of the string. Keep in mind v belts do stretch and unfortunately there is no specific given value for how much a belt stretches. You’ll also need to measure the width and depth to determine which section v belt you have.

All A,B,C,D,E,AX,BX belts list the inside circumference measurement after the letter of the v belt part number. Example: A88 has a 88″ inner circumference, then you add 2 inches for the A Section (Listed below) to obtain the outer circumference. If you measure the outer circumference, then you would subtract the number of inches based on the section you have (Listed below) to obtain the v belt number. This is also the same for the banded v belts. Measure each individual band for banded v belts to obtain the correct width.

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