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Head: From the posterior hairline to the Da Zhui bone (the depression below the spinous process of the seventh cervical vertebra), the length is 2.5 cun.
[Note] The proportional measurement method for the head: From the anterior hairline to the posterior hairline, it is measured as 12 cun. If the hairline is unclear, measure from the midpoint between the eyebrows straight up to the Da Zhu bone (located 1.5 cun lateral to the spinous process of the first thoracic vertebra), which is measured as 18 cun; this serves as the standard for vertical cun. For horizontal cun, the distance from the inner canthus to the outer canthus of the eye is defined as 1 cun. The horizontal and vertical cun measurements for the head are based on these standards. From Shen Ting (DU24) of the Du Meridian to Qu Cha (BL7) of the Taiyang Meridian, from Qu Cha to Ben Shen (GB13) of the Shaoyang Meridian, and from Ben Shen to Tou Wei (ST8) of the Yangming Meridian, each is 1.5 cun lateral. From Shen Ting to Tou Wei, each is 4.5 cun lateral.

Chest and Abdomen: From the laryngeal prominence to Que Pen (Clavicular Fossa Central), the middle length is 4 cun. (This refers to the depression above Ju Gu, which is the location of Tian Tu (CV22)). Below Que Pen, the middle length is 9 cun. The chest circumference is 4 chi 5 cun. The distance between the two nipples is 9.5 cun wide. (It should be calculated as 8 cun for accuracy). From Zhong Wan to Tian Shu, the length is 8 cun. (Tian Shu is an acupoint of the Foot-Yangming Stomach Meridian, located beside the umbilicus; here it refers to the level of the umbilicus). From Tian Shu to Heng Gu (Suprapubic Eminence), the length is 6.5 cun. The horizontal length of Heng Gu is 6.5 cun. (The bone below the pubic hair is called Heng Gu).
[Note] These are ancient numerical values. Comparing them with current methods for locating upper and lower acupoints, they often do not match. It is appropriate to adopt the subsequent proportional measurement method for the chest and abdomen.

Between the two thighs, the width is 6.5 cun. (This refers to the position of both ends of the transverse bone in the middle of the two thighs, commonly known as the thigh seam).
[Note] The proportional measurement method for the chest and abdomen: Vertical cun is based on the midline. Starting from Tian Tu (CV22) at Que Pen up to Zhong Ting (CV12) at the upper end of the sternal angle (xiphisternal junction), it is measured as 8.4 cun; from the sternal angle down to the center of the umbilicus, it is measured as 8 cun; from the center of the umbilicus down to Qu Gu (CV4) at the pubic symphysis, it is measured as 5 cun. Horizontal cun is based on the distance between the two nipples, measured as 8 cun. The horizontal and vertical cun measurements for the chest and abdomen are based on these standards.

Back: From the spine (vertebral column) to the sacrococcygeal region, comprising 21 segments, the length is 3 chi. (Lu bone refers to the spinal bone. The spine is small externally but large internally; humans can bear heavy loads because of the magnitude of this bone. There are 24 vertebral segments in total; the mention of 21 segments excludes the three cervical segments). The waist circumference is 4 chi 2 cun.
[Note] The proportional measurement method for the back: From Da Zhui (DU14) to the sacrococcygeal region, the total length is 3 chi. The upper seven segments are each 1.41 cun long, totaling 9.87 cun. The middle seven segments are each 1.61 cun long, totaling 11.27 cun. The fourteenth segment is level with the umbilicus. The lower seven segments are each 1.26 cun long, totaling 8.82 cun, summing to 2 chi 9.96 cun. The remaining 0.04 cun is a fractional remainder not fully accounted for. Vertical cun is based on this standard; horizontal cun uses the middle finger proportional cun method.

The internal width of the spinal column is 1 cun. Whenever the second row of acupoints 1.5 cun from the spine or the third row 3 cun from the spine is mentioned, the 1-cun width of the spine itself is excluded, and the calculation is made purely based on 1.5 cun or 3 cun. Therefore, the second row should be considered as 2 cun wide, and the third row as 3.5 cun wide.

Lateral Aspect: From the Zhu Gu (bone at the root of the neck/shoulder) descending to the invisible part in the axilla, the length is 4 cun. (Zhu Gu refers to the bone at the root of the neck). From the axilla to Ji Xie (the ninth rib end), the length is 1 chi 2 cun. (Ji Xie refers to the floating ribs). From Ji Xie to Bi Shu (root of the thigh, corresponding to Huan Tiao (GB30)), the length is 6 cun. (The thigh is called Gu; the upper part of the thigh is called Bi. The area below the Jian bone and above the thigh, where the two bones meet, is called Bi Shu, located at the acupoint Huan Tiao (GB30) of the Foot-Shaoyang Gallbladder Meridian). From Bi Shu to the center of the knee, the length is 1 chi 9 cun. From the upper margin of Heng Gu to the upper margin of the Neifu bone (medial condyle of tibia), the length is 1 chi 8 cun. (The edge of a bone is called Lian; the protruding bone beside the knee is called Fu Gu; the medial side is Neifu, and the lateral side is Waifu). From the upper margin of Neifu to its lower margin, the length is 3.5 cun. (Upper and lower margins can be palpated). From the lower margin of Neifu to the medial malleolus, the length is 1 chi 2 cun. From the medial malleolus to the ground, the length is 3 cun.

Limbs: From the shoulder to the elbow, the length is 1 chi 7 cun. From the elbow to the wrist, the length is 1 chi 2.5 cun. (The middle section of the arm is called Elbow). From the wrist to the base of the middle finger (metacarpophalangeal joint), the length is 4 cun. (The junction of the arm and palm is called Wrist). From the base of the finger to the tip, the length is 4.5 cun. (The distal phalanx is called the base segment). From the knee to the lateral malleolus, the length is 1 chi 6 cun. From the knee to the foot dorsum (Shu Shu), the length is 1 chi 6 cun. (The popliteal fossa is posterior; the foot dorsum is anterior. Shu Shu refers to the areas where the tibia and tarsus meet anteriorly and posteriorly around the ankles, all belonging to the dorsum). From Shu Shu to the ground, the length is 3 cun. From the lateral malleolus to the ground, the length is 1 cun. The length of the foot is 1 chi 2 cun, and its width is 4.5 cun.
[Note] The bone proportions discussed are from the "Bone Proportions" chapter of the *Ling Shu Jing* (Spiritual Pivot), representing ancient numerical standards. However, individuals with larger bones exceed these standards, while those with smaller bones fall short; thus, these figures merely provide general guidelines. For measuring the limbs and extremities of the whole body, the middle finger proportional cun method described earlier should be used.