Centimeter to Span Converter
Convert centimeters to spans with our free online length converter.
Quick Answer
1 Centimeter = 0.043745 spans
Formula: Centimeter × conversion factor = Span
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.
Centimeter to Span Calculator
How to Use the Centimeter to Span Calculator:
- Enter the value you want to convert in the 'From' field (Centimeter).
- The converted value in Span 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 Centimeter to Span: Step-by-Step Guide
Converting Centimeter to Span involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Centimeter = 0.0437445 spansExample Calculation:
Convert 10 centimeters: 10 × 0.0437445 = 0.437445 spans
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 Centimeter and a Span?
The centimeter (symbol: cm) is a unit of length equal to exactly one-hundredth of a meter (1/100 m or 0.01 m). It's also equal to exactly 10 millimeters.
The centimeter is part of the International System of Units (SI) and uses the metric prefix "centi-" meaning one-hundredth (from Latin centum, "hundred").
Mathematical Relationships
1 centimeter equals:
- 10 millimeters (mm)
- 0.01 meters (m)
- 0.00001 kilometers (km)
- 0.393701 inches (in)
- 0.0328084 feet (ft)
Key conversion:
- 1 inch = 2.54 cm exactly (this is the official international definition established in 1959)
Why Centimeters?
While the meter is the official SI base unit for length, centimeters are more practical for everyday measurements:
Too small for meters, too large for millimeters: A person who is 1.75 meters tall is more commonly described as 175 centimeters in metric countries. Writing "1.75 m" requires decimals; "175 cm" uses whole numbers.
Human-scale convenience: Most objects people interact with daily—clothing, screens, body measurements, food items—fall naturally into the 1-100 cm range.
Avoids decimal confusion: "15.2 cm" is clearer than "0.152 m" for most people.
The Span is an ancient unit of length based on the distance across an outstretched human hand, measured from the tip of the thumb to the tip of the little finger (or sometimes the index finger). As an anthropomorphic unit, its length was inherently variable, depending on the size of an individual's hand.
Historically, it was often defined in relation to other body-based units:
- Typically considered half a cubit.
- Often equated to 3 palms (where a palm is the width of the hand across the base of the fingers).
- Sometimes defined as 12 digits (fingerbreadths).
A common, though unofficial, modern estimate for a span is around 9 inches or approximately 22.86 centimeters (cm).
Note: The Centimeter is part of the metric (SI) system, primarily used globally in science and trade. The Span belongs to the imperial/US customary system.
History of the Centimeter and Span
French Revolution and the Birth of the Metric System
1790s: Revolutionary Innovation: The centimeter was born from the French Revolution's ambition to create a rational, universal measurement system based on nature and decimal mathematics.
The Meter Foundation: In 1791, the French Academy of Sciences defined the meter as one ten-millionth (1/10,000,000) of the distance from the equator to the North Pole along the meridian passing through Paris. The centimeter automatically followed as 1/100 of this meter.
Latin Roots: The prefix "centi-" derives from the Latin centum (hundred), making "centimeter" literally "hundredth of a meter."
1795 Official Adoption: France officially adopted the metric system on April 7, 1795, including the centimeter as a standard subdivision of the meter.
CGS System: The Centimeter's Scientific Era
1874: The Centimeter-Gram-Second System: British scientists James Clerk Maxwell and William Thomson (Lord Kelvin) promoted the CGS system, which used:
- Centimeter for length (instead of meter)
- Gram for mass (instead of kilogram)
- Second for time
Scientific Dominance: The CGS system became the preferred standard for physics and chemistry throughout the late 19th and early 20th centuries. Many scientific formulas and units were developed using centimeters.
Legacy Units: Several units still reflect the CGS heritage:
- Poise (viscosity): measured in gram/(centimeter·second)
- Erg (energy): gram·centimeter²/second²
- Gauss (magnetic field): CGS unit for magnetic flux density
Transition to SI and the Modern Era
1960: The SI System: The International System of Units (SI) was officially established, promoting the meter-kilogram-second (MKS) system instead of CGS.
Centimeter's Continued Relevance: Despite the official SI preference for meters, centimeters remained dominant for everyday measurements because:
- They're more practical for human-scale objects
- They avoid decimals for most common measurements
- They're familiar and intuitive
Global Adoption: Today, 195 of 198 countries use the metric system, with centimeters as the standard for body height, clothing, and everyday measurements. Only the United States, Myanmar, and Liberia officially use non-metric systems.
The span is one of the oldest informal units of measurement, used by numerous ancient civilizations, including the Egyptians, Israelites, Greeks, and Romans, due to the convenience of using the human hand.
- Ancient Egypt & Mesopotamia: The span was used alongside the cubit and digit. The relationship (often 1 span = 1/2 cubit) was fundamental in their systems.
- Biblical References: The span is mentioned in the Bible (e.g., Exodus 28:16 describing the High Priest's breastplate, Goliath's height in some interpretations).
- Ancient Greece & Rome: Used as a practical subdivision of the cubit.
- Medieval Europe: Continued in informal use and sometimes appeared in texts defining lengths. In England, it was often standardized (unofficially) as 9 inches.
Like other anthropomorphic units, the span fell out of official use with the development and adoption of more standardized systems like the Imperial (inches, feet) and Metric (meters) systems, which provided necessary precision for trade, science, and industry.
Common Uses and Applications: centimeters vs spans
Explore the typical applications for both Centimeter (metric) and Span (imperial/US) to understand their common contexts.
Common Uses for centimeters
Medical and Healthcare
Growth Charts: Children's height is tracked in centimeters from birth:
- Pediatricians plot growth on percentile charts
- Birth length recorded in cm (typically 45-55 cm)
- Annual height measurements track development
Medical Measurements:
- Wound size: "3 cm laceration"
- Tumor diameter: measured in cm for staging
- Organ size: "enlarged liver extending 4 cm below rib cage"
- Dilation during childbirth: measured in cm (0-10 cm)
Medical Equipment:
- Blood pressure cuff width: 12-13 cm for adults
- Surgical incision length: documented in cm
- Catheter diameter: measured in mm, length in cm
Education and School Supplies
Rulers and Measuring Tools: Most rulers worldwide show centimeters:
- Standard ruler: 15 cm or 30 cm length
- Meter stick: 100 cm with cm markings
- Tape measures: marked in cm (and meters)
Paper Sizes (International ISO 216 Standard):
- A4 paper: 21 × 29.7 cm (most common worldwide)
- A5 paper: 14.8 × 21 cm (half of A4)
- A3 paper: 29.7 × 42 cm (double A4)
- Letter size (US): 21.6 × 27.9 cm (8.5 × 11 inches)
School Supplies:
- Pencil length: 19 cm (new)
- Notebook width: 15-21 cm
- Eraser length: 4-6 cm
Construction and Home Improvement
Tile Sizes: Floor and wall tiles measured in cm:
- Small tiles: 10×10 cm
- Medium tiles: 30×30 cm
- Large format tiles: 60×60 cm or 80×80 cm
- Subway tiles: 7.5×15 cm
Furniture Dimensions:
- Coffee table height: 40-50 cm
- Dining table height: 75 cm (standard)
- Chair seat height: 45-50 cm
- Sofa seat depth: 50-60 cm
Door Measurements:
- Standard interior door width: 80-90 cm
- Standard door height: 200-210 cm
- Door thickness: 3.5-4.5 cm
Art, Design, and Photography
Photo Print Sizes:
- 10×15 cm (4×6 inches) - standard print
- 13×18 cm (5×7 inches)
- 20×25 cm (8×10 inches)
- 30×40 cm (12×16 inches)
Canvas and Frame Sizes: Art supply stores sell in metric:
- Small canvas: 20×25 cm
- Medium canvas: 30×40 cm
- Large canvas: 50×70 cm
Drawing and Design:
- Technical drawings: dimensioned in cm or mm
- Graph paper: 0.5 cm or 1 cm grids
- Architectural scales: often use 1:50 or 1:100 (cm-based)
Sports and Recreation
Swimming Pool Depth: Measured in cm or meters:
- Shallow end: 90-120 cm
- Deep end: 180-300 cm
- Competition pool depth: minimum 200 cm
Bicycle Frame Sizes: Road bikes measured in cm:
- Small frame: 48-52 cm
- Medium frame: 54-56 cm
- Large frame: 58-62 cm
Sports Equipment:
- Tennis ball diameter: 6.5-6.7 cm
- Golf ball diameter: 4.3 cm
- Basketball diameter: 24 cm
When to Use spans
The span is now obsolete for precise or official measurements but is still encountered or used in specific contexts:
- Informal Estimation: Used for quick, rough measurements of moderate lengths where precision is not critical (e.g., gardening, crafts, estimating object sizes).
- Historical Texts: Found in ancient and medieval documents, requiring understanding for interpretation.
- Anthropology & Archaeology: Relevant when studying historical measurement systems or interpreting dimensions from ancient sites.
- Figurative Language: Can be used metaphorically to denote a small distance or extent ("life span").
- Understanding Historical Units: Key to grasping the relationship between units like the digit, palm, and cubit in ancient systems.
Additional Unit Information
About Span (span)
How long is a span?
There is no single, universally fixed length for a span because it's based on human hand size. However:
- A common historical and modern estimate is 9 inches (in).
- This is approximately 22.86 centimeters (cm) or 0.2286 meters (m).
- Historically, it was often defined as half a cubit, which varied (e.g., a common cubit of ~18 inches would yield a 9-inch span).
What is the relationship between a span and a cubit?
In many historical systems, a span was considered half (1/2) of a cubit. Since cubits themselves varied (e.g., common cubit vs. royal cubit), the exact length of the span derived this way also varied.
What is the relationship between a span and a palm or digit?
Common relationships, though varying by system, were:
- 1 span ≈ 3 palms (where a palm is the width of the hand).
- 1 span ≈ 12 digits (where a digit is the width of a finger).
Is the span an SI unit?
No, the span is not an SI unit. It is an ancient, non-standardized, anthropomorphic unit. The SI base unit for length is the meter (m).
Is the span still used today?
The span is not used for any official, scientific, or commercial measurements. Its use is limited to informal estimations, historical context, and figurative language. People might still use their own hand span for a quick size check.
Where does the name 'span' come from?
The word "span" comes from Old English spann, related to the verb spannan, meaning "to stretch, extend, or connect". This directly reflects the action of stretching the hand to measure the unit.
Conversion Table: Centimeter to Span
| Centimeter (cm) | Span (span) |
|---|---|
| 0.5 | 0.022 |
| 1 | 0.044 |
| 1.5 | 0.066 |
| 2 | 0.088 |
| 5 | 0.219 |
| 10 | 0.437 |
| 25 | 1.094 |
| 50 | 2.187 |
| 100 | 4.375 |
| 250 | 10.936 |
| 500 | 21.872 |
| 1,000 | 43.745 |
People Also Ask
How do I convert Centimeter to Span?
To convert Centimeter to Span, enter the value in Centimeter 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 Centimeter to Span?
The conversion factor depends on the specific relationship between Centimeter and Span. 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 Span back to Centimeter?
Yes! You can easily convert Span back to Centimeter by using the swap button (⇌) in the calculator above, or by visiting our Span to Centimeter converter page. You can also explore other length conversions on our category page.
Learn more →What are common uses for Centimeter and Span?
Centimeter and Span 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.
Helpful Conversion Guides
Learn more about unit conversion with our comprehensive guides:
📚 How to Convert Units
Step-by-step guide to unit conversion with practical examples.
🔢 Conversion Formulas
Essential formulas for length and other conversions.
⚖️ Metric vs Imperial
Understand the differences between measurement systems.
⚠️ Common Mistakes
Learn about frequent errors and how to avoid them.
All Length Conversions
Other Length Units and Conversions
Explore other length units and their conversion options:
- Meter (m) • Centimeter to Meter
- Kilometer (km) • Centimeter to Kilometer
- Hectometer (hm) • Centimeter to Hectometer
- Decimeter (dm) • Centimeter to Decimeter
- Millimeter (mm) • Centimeter to Millimeter
- Inch (in) • Centimeter to Inch
- Foot (ft) • Centimeter to Foot
- Yard (yd) • Centimeter to Yard
- Mile (mi) • Centimeter to Mile
- Nautical Mile (NM) • Centimeter 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: February 19, 2026