Convert Centimeter to X-unit
Convert centimeters to x-units instantly. 1 centimeter = 9.979044e+10 x-unit — use the live calculator, the exact formula, a conversion table and worked examples. Also check the X-unit to Centimeter converter for the reverse conversion.
Units explained
Centimeter
A centimeter is a metric unit of length equal to one hundredth of a meter (1/100 m). It is one of the most commonly used SI sub-units in daily life, especially for measuring small objects, body dimensions, paper sizes, and short distances.
The centimeter emerged from the French metric system established by the French Academy of Sciences in 1793. The metric system introduced decimal-based prefixes (milli-, centi-, deci-, deca-, hecto-, kilo-) to create proportional sub-units of the meter.
Centimeters are the standard unit for everyday measurement in nearly every country outside the United States. They are used for body height, clothing sizes, rainfall, paper formats (A4 is 21 × 29.7 cm), screen dimensions, and most consumer product specifications.
Developed in France during the late 18th century as part of the metric system designed by the French Academy of Sciences. Formally adopted in France in 1795 and ratified internationally through the Metre Convention signed in Paris in 1875.
X-unit
The X-unit (or siegbahn) is a historical X-ray crystallography unit of approximately 1.0021×10⁻¹³ meters. It was used before X-ray wavelengths could be measured directly in meters.
Introduced by Manne Siegbahn in 1925 as a self-consistent unit for X-ray crystallography. The 'X-unit' was defined to make the X-ray wavelength of the molybdenum K-alpha line a round number.
X-units appear in X-ray crystallography literature from 1925 through the 1960s. Modern crystallography uses meters or angstroms; X-units are mostly of historical interest now.
Defined by Manne Siegbahn in 1925; superseded by direct SI measurement of X-ray wavelengths after the 1960s; retained in literature for historical comparison.
Centimeter to X-unit conversion formula
The relationship between centimeters and x-units:
To convert centimeters to x-units, multiply the value in centimeters by 9.979044e+10. To reverse, multiply x-units by 1.0021e-11.
How to use this converter
Type a value into the calculator. The result in x-units updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the X-unit to Centimeter converter for the reverse direction.
Step-by-step: convert centimeters to x-units
- Write down the value in centimeters (cm).
- Multiply that value by the factor 9.979044e+10.
- The product is the equivalent value in x-units (X).
- To reverse, multiply the x-unit value by 1.0021e-11.
Worked examples
Example 1 — Convert 1 cm to X:
1 × 9.979044e+10 = 9.979044e+10 X
Example 2 — Convert 100 cm to X:
100 × 9.979044e+10 = 9.979044e+12 X
Real-world example — Small-scale to atomic-scale
One centimeter equals 10 million x-units — useful for physics curricula that relate everyday measurements to atomic and optical scales.
1 cm × 9.979044e+10 = 9.979044e+10 X
Real-world example — Centimeter to wavelength scale
One centimeter equals 10 million x-units. Physics curricula use this kind of conversion to relate everyday measurements to atomic and optical scales.
1 cm × 9.979044e+10 = 9.979044e+10 X
Centimeter to X-unit conversion table
Standard reference values for converting centimeters to x-units:
| Centimeter [cm] | X-unit [X] |
|---|---|
| 0.01 | 9.979044e+8 |
| 0.1 | 9.979044e+9 |
| 1 | 9.979044e+10 |
| 2 | 1.995809e+11 |
| 3 | 2.993713e+11 |
| 4 | 3.991618e+11 |
| 5 | 4.989522e+11 |
| 10 | 9.979044e+11 |
| 20 | 1.995809e+12 |
| 30 | 2.993713e+12 |
| 40 | 3.991618e+12 |
| 50 | 4.989522e+12 |
| 100 | 9.979044e+12 |
| 500 | 4.989522e+13 |
| 1000 | 9.979044e+13 |
Frequently asked questions
How many x-units is 1 centimeter?
How do I convert centimeters to x-units?
How do I convert x-units back to centimeters?
How many x-units is 100 centimeters?
Popular length unit conversions
Convert Centimeter to other length units
Show all Centimeter conversions
Metric / SI (17 units)
Imperial / US Customary (27 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 cm = 9.979044e+10 X) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.