Japanese length converter

Convert shaku, sun, bu and ken to metric lengths and back, with the traditional convention made explicit. The selected conversion is followed by equivalents in every included unit.

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How it works

Formula

$Converted value = Value to convert \times Conversion multiplier$
$1 shaku = \frac{10}{33 m}$
$1 sun = \frac{1}{10 shaku}$
$1 bu = \frac{1}{100 shaku}$

1 ken = 6 shaku

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Your result

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Sources

MAFF — Japanese measurement conversion tableSources reviewed: 2026-10-30
National Diet Library — historical shaku definitionSources reviewed: 2026-10-30

Assumptions and limitations

Uses kanejaku: 1 shaku = 10/33 m and 1 ken = 6 shaku. Kujirajaku, regional building spans and historical variants are excluded.

How to use this tool

Set up the inputs

Enter the length and select the original and destination units. Check which shaku convention your document uses.

Worked examples

Read one ken on a timber plan

1 ken = 6 shaku = 20/11 m ≈ 1.81818182 m.

Frequently asked questions

How should I read the result from Japanese length converter?

The selected conversion is followed by equivalents in every included unit. Display precision does not improve the accuracy of an old measurement.

Processing and privacy

The calculation or transformation runs in your browser. The tool does not send its input values or generated output to an application server. Loading a page still makes infrastructure requests; optional analytics and Google consent messages have separate controls.

Help and feedback

Consult the linked sources for definitions and reference data. Contact Support if you have a question or notice a problem.

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Japanese length converter

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