On this page you will learn how to measure throws correctly in practice.
Shot put 
You need at least two people to measure a throw. When a shot lands it always leaves an indentation or divot in the ground. One person holds the zero point of the measuring tape at the point of the indentation which is closest to the inner edge of the circle and the other person pulls the tape through the middle of the circle so the tape is straight and taut. The second (or a third) person then reads the distance from the inside of the stop board, rounding down to the nearest centimetre.
Discus
You need at least two people to measure a throw. The person in the field marking where the discus lands needs to watch the discus carefully as the landing discus doesn’t always leave an impression in the ground, depending on how it lands. If it lands flat there may not be a visible mark at all. The person marking where the discus lands holds the zero point of the tape at the point of the indentation which is closest to the edge of the circle and the other person pulls the tape through the middle of the circle so the tape is straight and taut. The second (or a third) person then reads the distance from the inside of the circle, rounding down to the nearest centimetre.
Javelin
You need at least three people to measure a throw accurately. The person in the field marking where the javelin lands needs to watch the implement carefully as the landing javelin doesn’t always leave an impression in the ground, depending on how it lands. If it lands fairly flat there may not be a visible mark at all depending on the condition of the surface. The person marking where the javelin lands holds the zero point of the tape at the point of the indentation which is closest to the inner edge of the throwing arc or at the point where the tip of the javelin (the metal part) first touched the ground. A second person who is located near the runway pulls the tape through the centre of the circle of which the throwing arc is part so the tape is straight and taut. The third person then reads the distance from the inside of the throw line/arc, rounding down to the nearest centimetre. If there are only two people available for measuring, the person pulling the tape through should hold the tape at the part of the correct point of the throwing line/arc.
Hammer
You need at least two people to measure a throw. When a hammer lands it always leaves an indentation or divot in the ground.The person marking where the hammer lands holds the zero point of the tape at the point of the indentation which is closest to the inner edge of the circle and the other person pulls the tape through the middle of the circle so the tape is straight and taut. The second (or a third) person then reads the distance from the inside of the circle, rounding down to the nearest centimetre.