Shaku (Japanese) to Millimeter Converter
Convert shaku to millimeters with our free online length converter.
Quick Answer
1 Shaku (Japanese) = 303 millimeters
Formula: Shaku (Japanese) × conversion factor = Millimeter
Use the calculator below for instant, accurate conversions.
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All conversion formulas on UnitsConverter.io have been verified against NIST (National Institute of Standards and Technology) guidelines and international SI standards. Our calculations are accurate to 10 decimal places for standard conversions and use arbitrary precision arithmetic for astronomical units.
Shaku (Japanese) to Millimeter Calculator
How to Use the Shaku (Japanese) to Millimeter Calculator:
- Enter the value you want to convert in the 'From' field (Shaku (Japanese)).
- The converted value in Millimeter will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Length category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Shaku (Japanese) to Millimeter: Step-by-Step Guide
Converting Shaku (Japanese) to Millimeter involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Shaku (Japanese) = 303 millimetersExample Calculation:
Convert 10 shaku: 10 × 303 = 3030 millimeters
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
Need to convert to other length units?
View all Length conversions →What is a Shaku (Japanese) and a Millimeter?
The Shaku (尺) is a traditional Japanese unit of length, forming a fundamental part of the traditional Japanese system of weights and measures known as the Shakkanhō (尺貫法). It is roughly equivalent to the English foot, although slightly shorter in its modern standardized form.
The Shaku is traditionally subdivided and multiplied decimally:
- 1 Jō (丈) = 10 Shaku
- 1 Shaku (尺) = 10 Sun (寸 - Japanese inch)
- 1 Sun (寸) = 10 Bu (分 - Japanese line)
There were historically different types of shaku, most notably the standard kanejaku (曲尺) used in carpentry and the longer kujirajaku (鯨尺) used for measuring cloth. Unless otherwise specified, "shaku" usually refers to the kanejaku.
The millimeter (symbol: mm) is a unit of length in the metric system equal to one-thousandth of a meter (1/1,000 m) or one-tenth of a centimeter (1/10 cm). It is used for precise measurements in engineering, manufacturing, and everyday applications.
Key relationships:
- 1 millimeter = 0.001 meters (m)
- 1 millimeter = 0.1 centimeters (cm)
- 10 millimeters = 1 centimeter
- 1,000 millimeters = 1 meter
- 1 millimeter ≈ 0.03937 inches (about 1/25th inch)
- 25.4 millimeters = 1 inch (exactly)
The prefix "milli-":
- From Latin "mille" meaning "thousand"
- SI prefix denoting 10⁻³ (one-thousandth)
- Also used in: milligram (mg), milliliter (mL), millisecond (ms)
Visual perspective (how big is it?):
- 1 mm = Thickness of a credit card
- 2 mm = Thickness of a US dime
- 5 mm = Thickness of a pencil lead (mechanical)
- 10 mm = Width of an adult fingernail
- 25.4 mm = Exactly one inch
Convert between length units: mm converter
Note: The Shaku (Japanese) is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Millimeter belongs to the metric (SI) system.
History of the Shaku (Japanese) and Millimeter
The Shaku originated from the Chinese Chi (尺), introduced to Japan likely between the 3rd and 6th centuries AD. Like its Chinese counterpart, the length of the Shaku varied considerably across different historical periods and regions in Japan.
- Early Adoption: Early Japanese measurements were heavily influenced by Chinese standards, but the length of the Shaku began to diverge over time.
- Edo Period (1603–1868): Different standards coexisted, including the kanejaku (carpenter's shaku) and the kujirajaku (cloth shaku, literally "whale shaku," possibly referring to rulers made from whale baleen). The kanejaku became the more common standard for general measurement.
- Meiji Restoration (1868 onwards): Japan began modernizing and standardizing its systems. In 1891, the Weights and Measures Act defined the standard Shaku (kanejaku) legally in relation to the metric system as exactly 10/33 of a meter. This aimed to provide a precise conversion factor while preserving the traditional unit. The kujirajaku was defined as 1.25 times the kanejaku (i.e., 12.5/33 of a meter).
- Metrication: Japan officially adopted the metric system in 1951, and its use became mandatory for most official and commercial transactions by 1966. However, the Shaku and other Shakkanhō units remain in use in specific traditional fields.
-
Metric System Origins: The millimeter was defined as a subunit of the meter when the metric system was established in France during the late 18th century (1790s). As measurement standardization progressed, the need for decimal subdivisions of the meter became clear.
-
Industrial Revolution: The millimeter became essential during the 19th century Industrial Revolution as:
- Precision machining required fine tolerances
- Interchangeable parts manufacturing emerged
- Engineering drawings needed standard units
- Technical specifications became international
-
Engineering Adoption: By the mid-19th century, engineers and machinists worldwide adopted millimeters as the standard for:
- Machine tool specifications
- Tolerance requirements (±0.1 mm common)
- Technical drawing dimensions
- Quality control measurements
-
Scientific Standardization: The millimeter became standard in scientific research for:
- Laboratory equipment calibration
- Microscopy measurements
- Specimen documentation
- Experimental apparatus dimensions
-
SI Formalization: When the International System of Units (SI) was established in 1960, the millimeter was confirmed as an official subdivision of the meter, forming part of the coherent decimal system.
-
Modern Manufacturing: The 20th century saw millimeters become universal in:
- Automotive engineering specifications
- Electronics manufacturing (PCB design)
- Aerospace tolerances
- Medical device specifications
- Consumer product dimensions
-
Global Standard: Today, millimeters are the primary unit for precision measurements in virtually every country except the United States (which uses both mm and inches). Even in the US, many technical fields have adopted millimeters as standard.
Common Uses and Applications: shaku vs millimeters
Explore the typical applications for both Shaku (Japanese) (imperial/US) and Millimeter (metric) to understand their common contexts.
Common Uses for shaku
While the metric system is standard in Japan, the Shaku persists in several areas:
- Traditional Japanese Architecture and Carpentry: The kanejaku is still widely used for measurements in building temples, shrines, traditional houses, and making furniture. Architectural modules like the ken (間) are often based on the Shaku. Japanese woodworking tools are often sized or marked in Shaku and Sun.
- Kimono and Traditional Clothing: The kujirajaku is the standard unit for measuring cloth width (tanmono) and dimensions when making kimonos and yukatas.
- Traditional Crafts: Used in making items like tatami mats, shōji screens, and other traditional crafts where historical dimensions are important.
- Musical Instruments: The length of traditional Japanese instruments, notably the shakuhachi (尺八) flute, is measured in Shaku and Sun (its name literally means "1.8 shaku").
- Martial Arts: Some traditional martial arts (koryū budō) may use Shaku-based measurements for weapon lengths (e.g., jō, bō) or stance dimensions.
- Gardening and Landscaping: Traditional Japanese garden design sometimes employs Shaku-based proportions.
- Historical and Cultural Context: Essential for understanding dimensions in historical texts, art, and artifacts.
When to Use millimeters
The millimeter is the standard unit for precise measurements across multiple fields:
Engineering & Machining
Precise measurement requirements for manufacturing, quality control, and technical specifications. Essential for maintaining tolerances in mechanical parts.
Why millimeters in engineering:
- Decimal system (easy calculations)
- International standard (ISO)
- Suitable precision range
- Compatible with CNC machinery
- Standard drawing units
Applications:
- Machine tool specifications
- Part tolerances (±0.05 mm common)
- Technical drawing dimensions
- CAD/CAM software units
- Quality inspection reports
Convert for technical work: mm to inches | mm to cm
Technical Design & Drafting
Standard measurement unit for architectural, mechanical, and technical drawings worldwide.
Drawing Standards:
- ISO standards use millimeters
- Engineering drawings in mm
- Architecture plans (many countries)
- Product design specifications
- Patent drawings (international)
Why mm for drawings:
- Eliminates fractions (unlike inches)
- Scales easily (1:10, 1:100, etc.)
- International communication
- CAD software standard
Electronics & PCB Design
Measuring component sizes, trace widths, and circuit board dimensions in electronic manufacturing.
PCB Design:
- Trace width: 0.25-1 mm
- Component footprints: mm specifications
- Hole diameters: 0.6-1.2 mm
- Board thickness: 1.6 mm standard
- Component spacing: mm grid
Component Specs:
- All modern ICs specified in mm
- Resistor/capacitor sizes (mm codes)
- Connector dimensions
- Display module sizes
Meteorology & Climate
Measuring rainfall amounts with precision, essential for weather forecasting, agriculture, and climate research.
Rain Gauges:
- Standard measurement unit worldwide
- Collected in graduated cylinders (mm scale)
- Automated weather stations use mm
- Historical records in mm
- Climate data standardized
Importance:
- Drought assessment
- Flood prediction
- Agricultural planning
- Water resource management
- Climate change tracking
Use our mm converter for scientific calculations.
Manufacturing & Quality Control
Inspecting product dimensions and ensuring parts meet specifications within required tolerances.
QC Measurements:
- Caliper readings in mm
- Micrometer measurements
- Coordinate measuring machines (CMM)
- Surface profile measurements
- Dimensional inspection reports
Industries:
- Automotive parts
- Aerospace components
- Medical devices
- Consumer electronics
- Precision instruments
Jewelry & Watchmaking
Specifying sizes of gems, watch cases, and jewelry components with precision.
Why jewelers use mm:
- International gem standard
- Precise size communication
- Watch industry standard
- Setting specifications
- Customer communication
Measurements:
- Gemstone dimensions
- Ring widths and thicknesses
- Watch case diameters
- Bracelet link sizes
- Clasp dimensions
Medical Measurements
Documenting precise measurements in diagnostics, surgery planning, and treatment monitoring.
Clinical Uses:
- Imaging measurements (CT, MRI, X-ray)
- Tumor size tracking
- Surgical planning
- Needle specifications
- Medical device dimensions
Why mm in medicine:
- International standard
- Appropriate precision
- Imaging system default
- Research compatibility
- Treatment standardization
Additional Unit Information
About Shaku (Japanese) (shaku)
How long is a Shaku?
The length depends on the context (historical vs. modern, type of shaku):
- Modern Standardized Kanejaku (since 1891):
- Exactly 10/33 meters (m)
- Approximately 0.30303 meters
- Approximately 30.303 centimeters (cm)
- Approximately 11.93 inches (in)
- Approximately 0.994 feet (ft)
- Modern Standardized Kujirajaku:
- Exactly 12.5/33 meters (m) (1.25 times the kanejaku)
- Approximately 0.37879 meters
- Approximately 37.879 centimeters (cm)
- Approximately 14.91 inches (in)
- Approximately 1.243 feet (ft)
- Historical Shaku: Varied significantly, often differing from the modern standard.
What are the subdivisions and multiples of the Shaku?
The system is decimal:
- Subdivisions: 1 Shaku = 10 Sun (寸); 1 Sun = 10 Bu (分).
- Multiples: 1 Jō (丈) = 10 Shaku. Another related unit is the Ken (間), traditionally 6 Shaku, though its length could vary.
Is it the same as the Chinese Chi?
No. Although the Japanese Shaku originated from the Chinese Chi (both written with the character 尺), they evolved independently and have different standardized lengths today.
- Modern Japanese Shaku (kanejaku): 10/33 meters (≈ 0.303 m)
- Modern Chinese Chi: 1/3 meter (≈ 0.333 m) The Shaku is noticeably shorter than the modern Chi.
What is the difference between kanejaku and kujirajaku?
They are two distinct traditional Shaku units:
- Kanejaku (曲尺): The "carpenter's shaku," used for general measurement, architecture, and woodworking. Standardized at 10/33 meters. This is the default meaning of "Shaku."
- Kujirajaku (鯨尺): The "cloth shaku" or "whale shaku," used primarily for measuring cloth, especially for kimonos. It is longer than the kanejaku, standardized at 12.5/33 meters (exactly 1.25 times the kanejaku).
Is the Shaku an SI unit?
No, the Shaku is not an SI unit. It is a traditional Japanese unit belonging to the Shakkanhō system. The SI base unit for length is the meter (m).
Is the Shaku still used today?
Yes, although Japan officially uses the metric system (SI units) for most purposes, the Shaku (both kanejaku and kujirajaku) continues to be used in specific traditional fields:
- Traditional architecture and carpentry.
- Kimono making and textile measurement.
- Other traditional crafts.
- Musical instrument making (e.g., shakuhachi).
- Historical and cultural studies. It is generally not used in everyday commerce or scientific contexts.
About Millimeter (mm)
How many millimeters are in a centimeter?
There are exactly 10 millimeters (mm) in 1 centimeter (cm).
Conversion:
- 1 cm = 10 mm
- To convert cm to mm: multiply by 10
- To convert mm to cm: divide by 10
Examples:
- 5 cm = 50 mm
- 2.5 cm = 25 mm
- 75 mm = 7.5 cm
Memory aid: "Centi-" means 1/100 meter, "milli-" means 1/1,000 meter, so 10 mm = 1 cm.
Use our cm to mm converter for instant conversions.
How many millimeters are in a meter?
There are exactly 1,000 millimeters (mm) in 1 meter (m).
Conversion:
- 1 m = 1,000 mm
- To convert m to mm: multiply by 1,000
- To convert mm to m: divide by 1,000
Examples:
- 0.5 m = 500 mm
- 1.5 m = 1,500 mm
- 2,750 mm = 2.75 m
Remember: "Milli-" means one-thousandth, so it takes 1,000 mm to make 1 meter.
Convert: mm to meters | meters to mm
What does 'milli' mean in millimeter?
The prefix 'milli-' denotes one-thousandth (1/1,000).
Meaning:
- Comes from Latin "mille" meaning "thousand"
- In metric system: milli- = 10⁻³ = 1/1,000
- 1 millimeter = 1/1,000 of a meter = 0.001 m
Other "milli-" units:
- Milligram (mg) = 1/1,000 gram
- Milliliter (mL) = 1/1,000 liter
- Millisecond (ms) = 1/1,000 second
- Milliamp (mA) = 1/1,000 ampere
Pattern: Always divide by 1,000 to get the base unit.
How thick is 1 millimeter?
1 millimeter is very thin - about the thickness of:
Common objects:
- Credit card: 0.76 mm (slightly thinner)
- US dime: 1.35 mm (slightly thicker)
- 10 sheets of paper: ~1 mm
- Paperclip wire: ~1 mm diameter
- Mechanical pencil lead (0.7mm): Slightly thinner
Visual comparison:
- Thinner than a US penny (1.55 mm)
- About 1/25th of an inch (0.04 inches)
- 10 millimeters = 1 cm = width of fingernail
To visualize: Look at the edge of a credit card - that's less than 1 mm.
How many mm in an inch?
1 inch = 25.4 millimeters exactly (by international agreement).
This is a defined conversion (not an approximation):
- 1 inch ≡ 25.4 mm (exact)
- 1 mm = 1/25.4 inch ≈ 0.03937 inches
Common conversions:
- 1 inch = 25.4 mm
- 2 inches = 50.8 mm
- 3 inches = 76.2 mm
- 4 inches = 101.6 mm
- 12 inches (1 foot) = 304.8 mm
Reverse examples:
- 10 mm ≈ 0.394 inches
- 25 mm ≈ 0.984 inches (almost 1 inch)
- 50 mm ≈ 1.969 inches (almost 2 inches)
Memory trick: 25 mm is almost 1 inch (close enough for quick estimates).
Use our inch to mm converter for precise conversions.
What is 10mm in real life?
10 millimeters = 1 centimeter - about the width of an adult fingernail.
Common 10mm objects:
- Fingernail width (adult index finger)
- AA battery diameter: 14 mm (close)
- Small marble: ~10-15 mm diameter
- M10 bolt diameter: 10 mm
- Thick cardboard: ~10 mm
Comparisons:
- Just under 0.4 inches (0.394 inches exactly)
- Thickness of 100 sheets of paper
- About 3/8 inch (slightly larger)
In measurements:
- Camera/phone thickness: Often 7-10 mm
- Watch case thickness: Often 10-12 mm
- Pencil diameter: ~7-8 mm (10mm would be thick)
How do you read a metric ruler?
Metric rulers are divided into centimeters (cm) and millimeters (mm):
Reading steps:
- Large numbers: Centimeters (0, 1, 2, 3...)
- Long lines: Each centimeter mark
- Short lines: Millimeters (10 per cm)
- Count: From zero to your measurement point
Example reading:
- Between 3 and 4 cm, at the 7th small line = 3.7 cm or 37 mm
- At the 15th cm mark = 15 cm or 150 mm
Tips:
- 10 small marks = 1 cm
- Each small mark = 1 mm
- Halfway between cm marks = 5 mm
- Read to nearest 0.5 mm for precision
Reporting:
- Small objects: Use mm (e.g., "15 mm")
- Larger objects: Use cm (e.g., "15.5 cm")
- Both are correct, choose clearer one
What tools measure millimeters?
Many tools measure in millimeters:
Hand Tools:
- Metric ruler: Basic measurement to 1 mm
- Metric tape measure: Construction/carpentry
- Caliper: Precision to 0.01 mm (digital/vernier)
- Micrometer: Very precise, to 0.001 mm
- Depth gauge: Measuring depths and heights
Digital Tools:
- Digital caliper: Easy reading, 0.01 mm precision
- Laser distance meter: Millimeter accuracy
- Height gauge: Vertical measurements
- Coordinate measuring machine (CMM): Industrial precision
Specialized Tools:
- Feeler gauge: Thin strips in mm thicknesses
- Thread gauge: Checking thread pitch (mm)
- Bore gauge: Internal diameter measurement
- Pin gauge: Precision hole measurement
Which to use:
- Ruler: General purpose (±0.5 mm)
- Caliper: Precision work (±0.01 mm)
- Micrometer: Very tight tolerances (±0.001 mm)
Is mm smaller than cm?
Yes, millimeters (mm) are smaller than centimeters (cm).
Relationship:
- 1 cm = 10 mm
- 1 mm = 0.1 cm
- Millimeter is 10 times smaller than centimeter
Scale comparison:
- Largest: meter (m)
- Middle: centimeter (cm) = 1/100 m
- Smallest: millimeter (mm) = 1/1,000 m
Visual:
- Width of fingernail: 1 cm = 10 mm
- Thickness of dime: 1.35 mm (can't easily express in cm)
When to use each:
- Use mm: Small, precise measurements (< 100 mm)
- Use cm: Medium measurements (1-100 cm)
- Use m: Large measurements (> 1 meter)
Example:
- Pencil length: 19 cm or 190 mm (19 cm clearer)
- Wire diameter: 2 mm (not 0.2 cm - awkward)
How much rain is 1mm?
1 millimeter of rain means 1 mm depth of water would cover a flat surface if none drained away.
What it means:
- 1 mm rain = 1 liter per square meter of water
- Light drizzle might produce 1-2 mm/hour
- Barely enough to wet the ground thoroughly
Rain intensity scale:
- Trace-1 mm: Very light drizzle
- 1-2 mm: Light rain
- 2-5 mm: Light to moderate rain
- 5-10 mm: Moderate rain
- 10-20 mm: Heavy rain
- 20-50 mm: Very heavy rain
- >50 mm: Extreme rainfall (per hour)
Practical impact:
- 1 mm: Barely wets surfaces
- 10 mm: Significant watering
- 25 mm: Heavy rain event
- 100 mm: Major storm (in 24 hours)
Measurement:
- Rain gauge collects water
- Depth measured in mm
- Standard worldwide for weather reporting
Conversion Table: Shaku (Japanese) to Millimeter
| Shaku (Japanese) (shaku) | Millimeter (mm) |
|---|---|
| 0.5 | 151.5 |
| 1 | 303 |
| 1.5 | 454.5 |
| 2 | 606 |
| 5 | 1,515 |
| 10 | 3,030 |
| 25 | 7,575 |
| 50 | 15,150 |
| 100 | 30,300 |
| 250 | 75,750 |
| 500 | 151,500 |
| 1,000 | 303,000 |
People Also Ask
How do I convert Shaku (Japanese) to Millimeter?
To convert Shaku (Japanese) to Millimeter, enter the value in Shaku (Japanese) in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our length converter page to convert between other units in this category.
Learn more →What is the conversion factor from Shaku (Japanese) to Millimeter?
The conversion factor depends on the specific relationship between Shaku (Japanese) and Millimeter. You can find the exact conversion formula and factor on this page. Our calculator handles all calculations automatically. See the conversion table above for common values.
Can I convert Millimeter back to Shaku (Japanese)?
Yes! You can easily convert Millimeter back to Shaku (Japanese) by using the swap button (⇌) in the calculator above, or by visiting our Millimeter to Shaku (Japanese) converter page. You can also explore other length conversions on our category page.
Learn more →What are common uses for Shaku (Japanese) and Millimeter?
Shaku (Japanese) and Millimeter are both standard units used in length measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our length converter for more conversion options.
For more length conversion questions, visit our FAQ page or explore our conversion guides.
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⚖️ Metric vs Imperial
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⚠️ Common Mistakes
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All Length Conversions
Other Length Units and Conversions
Explore other length units and their conversion options:
- Meter (m) • Shaku (Japanese) to Meter
- Kilometer (km) • Shaku (Japanese) to Kilometer
- Hectometer (hm) • Shaku (Japanese) to Hectometer
- Decimeter (dm) • Shaku (Japanese) to Decimeter
- Centimeter (cm) • Shaku (Japanese) to Centimeter
- Inch (in) • Shaku (Japanese) to Inch
- Foot (ft) • Shaku (Japanese) to Foot
- Yard (yd) • Shaku (Japanese) to Yard
- Mile (mi) • Shaku (Japanese) to Mile
- Nautical Mile (NM) • Shaku (Japanese) to Nautical Mile
Verified Against Authority Standards
All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.
National Institute of Standards and Technology — Official US standards for length measurements
Bureau International des Poids et Mesures — International System of Units official documentation
Last verified: December 3, 2025