Shakuhachi size guide: Understanding Shaku Lengths

The shaku (尺) or ‘Japanese foot’ is an antiquated unit of length equivalent to 30.3 centimeters, approximately 11.9 inches (a different shaku of 37.9 cm / 14.9 inches is used by traditional Japanese tailors).

The word shakuhachi (尺八) refers to the standardized length of 1.8 shaku for these instruments. It’s an abbreviation of ichi-shaku-hachi-sun. However, shakuhachi has become the umbrella term used to refer to any length or key. A literal 1.8 shakuhachi will often be in the key of D4.

Shakuhachi Length and Pitch Discrepancies

Various factors can cause minor or major discrepancies between the length of an and the expected pitch. For this reason, it’s often necessary and recommended for shakuhachi craftspeople to provide the precise pitch at room temperature along with the exact length.

Common Shakuhachi Lengths and Keys

While the following shaku lengths are based on a precise 1 shaku = 30.3 cm conversion, actual lengths and pitches can vary slightly due to other dimensions and aspects of their construction. Therefore, this chart provides a general length for a given key.

• 1.5 shaku: 45± cm, Key of F4
• 1.6 shaku: 48± cm, Key of E4
• 1.7 shaku: 51± cm, Key of Eb4
• 1.8 shaku: 54± cm, Key of D4
• 1.9 shaku: 57± cm, Key of Db4
• 2.0 shaku: 60± cm, Key of C4
• 2.1 shaku: 63± cm, Key of B3
• 2.2 shaku: 66± cm, Key of Bb3
• 2.3-2.4 shaku: 72± cm, Key of A3
• 2.5-2.6 shaku: 76± cm, Key of Ab3
• 2.7-2.8 shaku: 82± cm, Key of G3
• 2.9-3.0 shaku: 89± cm, Key of F3
• 3.1 shaku: 94± cm, Key of E3
• 3.2 shaku: 97± cm, Key of Eb3
• 3.3 shaku: 100± cm, Key of D3

To delve deeper into the nuances of pitch and tuning, please refer to the page Understanding Shakuhachi Pitch and Tuning.