length · China / East Asia · Historical–modern

shaku

exact

Record: M235
Definition quality: Standardized historical Japanese shakkan reference
Conversion mode: multiplicative
Calculator: Fully calculable

Definition

Former Japanese law defines shaku as 10/33 metre; NDL gives approx. 30.3 cm.

Reference value

One shaku is equal to 0.3030303 metres.

Modern use

Modern-use scope is context-dependent; the website should follow the record's current-status and regional/system labels rather than imply universal use.

Did you know?

Unlike many ancient units, the modernized shaku received an exact metric legal definition.

Sources & evidence

Source tier Tier B/C — recorded secondary/reference source · confidence High

Related measurements

metre

length · International · Modern

SI base unit of length. Its definition fixes the speed of light in vacuum at exactly 299,792,458 m/s, with the second defined from the caesium-133 hyperfine frequency.