Ri (Japanese) to Centimeters (ri to cm)

1 ri (Japanese) equals 392,727.2727 centimeters (rounded).

1 ri (Japanese) = 392,727.2727 centimeters

How to convert ri (Japanese) to centimeters

To convert ri (Japanese) to centimeters, multiply the number of ri (Japanese) by 392,727.2727. The factor is rounded to 10 significant digits. To go the other way, multiply centimeters by 0.000002546296296 (rounded).

centimeters = ri (Japanese) × 392,727.2727

Example: 10 ri (Japanese) = 3,927,272.727 centimeters.

About these units

Ri (Japanese) (ri)

JapaneseTraditional unit (still used in some regions)

36 chō, about 3.927 km. The traditional Japanese 'mile', roughly an hour's walk.

Ri comes from the Chinese li, written with characters said to combine field and earth, hinting at the span of a village. China's li has varied widely, from about 323 meters under the Tang to exactly 500 meters in the modern standard, so a bare reference to a ri is ambiguous without context.

Early Japanese practice used a ri of six cho, around 500 to 600 meters. Later it came to mean the distance a loaded porter could cover on a mountain road in an hour, which gave versions of 36, 40 and 48 cho. The Tokugawa shogunate fixed 36 cho, and the 1891 law adopted that count as 216/55 kilometer, about 3.927 kilometers or 2.44 miles.

Modern distances use kilometers, leaving the ri in proverbs and literature, where it suggests roughly an hour's walk. Because the length changed over time and by region, a distance quoted in ri from an old text should not be converted without knowing which ri was meant.

1 ri (Japanese) = 3,927.272727 meters (approximately).

Sources: Wikipedia: Ri (unit); Wikipedia: Japanese units of measurement; Japanese Wikipedia: Shakkanho (尺貫法)

Centimeter (cm)

Metric (SI)Current unit

One hundredth of a meter. Used for body measurements, clothing and everyday objects.

Scientists, rather than shopkeepers, gave the centimeter its place. In 1832 Carl Friedrich Gauss proposed a system of absolute units built on length, mass and time, choosing the millimeter, milligram and second. In 1873 a committee of the British Association for the Advancement of Science, whose members included James Clerk Maxwell and William Thomson (Lord Kelvin), recommended the centimeter, gram and second instead. That CGS system dominated physics for decades, until the metre-kilogram-second system replaced it in the mid-twentieth century and led to SI.

CGS units proved awkward for rooms and buildings, which run to hundreds of centimeters, but the centimeter itself never went away. It is still the everyday unit for height, clothing and small objects, and it appears in map scales and rainfall reports. An adult fingernail is roughly one centimeter wide, and a milliliter is defined as exactly one cubic centimeter. An inch is exactly 2.54 centimeters. The CGS system itself survives mainly in theoretical physics and astrophysics, where Gaussian units are still common.

1 centimeter = 0.01 meters (exactly).

Sources: Wikipedia: Centimetre-gram-second system of units; Wikipedia: Centimetre; NIST Guide to the SI, Appendix B.8: conversion factors

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