Shoe size "Footwear - Sizing - Vocabulary and terminology"; currently in development are companion standards ISO/TS 19409 "Footwear - Sizing - Measurement of last dimensions" and ISO/TS 19410 "Footwear - Sizing - Inshoe measurement". The adult shoe sizes are calculated from typical last length, which is converted from foot length in mm by adding an allowance of two shoe sizes: where formula_13 is foot length in mm. Direct conversion between adult UK, European and Mondopoint shoe size systems is derived as follows: Exact foot lengths may contain repeating decimals because the formulas include division by 3; in practice, approximate interval steps of
Shoe size , Mexico, and European countries. Mondopoint system is also used by NATO and other military services. The standard is maintained by ISO Technical Committee 137 "Footwear sizing designations and marking systems"; as of 2018, a new revision is under development. In Japan, Taiwan and South Korea, the Mondopoint system is used as defined by national standard JIS S 5037:1998 and its counterparts CNS 4800-S1093:2000 and KS M 6681:2007. Foot length and girth (foot circumference) are taken into account. The foot length is indicated in centimetres; an increment of 5 mm is used. The length is followed by designators for girth