An astronomical unit is the mean Earth-Sun distance.
Astronomical units to Centimeters Converter — AU to cm
Convert Astronomical unit (AU) to Centimeter (cm) using the exact conversion factor (1 astronomical unit = 1.495979e+13 centimeter). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Astronomical units to Centimeters converter
Converter
Length Converter
Convert SI, imperial, US customary, astronomical, scientific, and historical length units.
Context values
Some unit families need one extra value for a physically accurate result.
Centimeter is 0.01 meter units.
Result = input x 1.49597871e+11 / 0.01.
Length uses the meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Astronomical units to Centimeters
Astronomical unit and Centimeter both measure length. Astronomical unit is typically associated with used internationally in astronomy for solar-system-scale distances., while Centimeter is typically associated with standard small-length unit worldwide except the US.
Formula
centimeters = astronomical units × 1.495979e+13
This factor comes from each unit's defined relationship to the category's base unit: 1 astronomical unit equals 149597870700 base units, and 1 centimeter equals 0.01 base units, so dividing one by the other gives the direct astronomical unit-to-centimeter factor of 1.495979e+13.
Simple example
1 AU × 1.495979e+13 = 1.495979e+13 cm
1 astronomical unit = 1.495979e+13 centimeters.
Real-world example
10 AU × 1.495979e+13 = 1.495979e+14 cm
10 astronomical units = 1.495979e+14 centimeters.
Conversion table
| Astronomical unit (AU) | Centimeter (cm) |
|---|---|
| 1 AU | 1.495979e+13 cm |
| 5 AU | 7.479894e+13 cm |
| 10 AU | 1.495979e+14 cm |
| 21.0975 AU | 3.156141e+14 cm |
| 42.195 AU | 6.312282e+14 cm |
| 100 AU | 1.495979e+15 cm |
Reverse conversion: Centimeter to Astronomical unit
1.495979e+13 cm × 6.684587e-14 = 1.000000196 AU
1.495979e+13 centimeters = 1.000000196 astronomical units.
astronomical units = centimeters × 6.684587e-14
For a page dedicated to this direction, see Centimeter to Astronomical unit.
Astronomical unit vs. Centimeter
| Aspect | Astronomical unit | Centimeter |
|---|---|---|
| Family | Non-SI unit accepted for use with SI (astronomical) | SI derived (metric prefix) unit |
| Typical use | Measuring distances within the solar system (planetary orbits) | Everyday small-object and body measurement (height, clothing sizes) outside the US |
| Where it's used | Used internationally in astronomy for solar-system-scale distances. | Standard small-length unit worldwide except the US |
Understanding the Astronomical unit
Astronomical unit (AU) measures distance. The astronomical unit is defined as exactly 149,597,870,700 meters, close to the average Earth-Sun distance. It is classified as a Non-SI unit accepted for use with SI (astronomical).
Where it's used: Used internationally in astronomy for solar-system-scale distances.
Uses of the Astronomical unit today
- Measuring distances within the solar system (planetary orbits)
- Astronomical calculations and spacecraft navigation
- Popular science communication about the solar system
History of the Astronomical unit
The astronomical unit originated from 17th-19th century attempts to measure the Earth-Sun distance, refined over time using transits of Venus and later radar and spacecraft ranging.
In 2012, the International Astronomical Union fixed the AU at exactly 149,597,870,700 meters, replacing its earlier definition (tied to gravitational calculations) with a simple fixed distance, independent of the slightly-variable actual Earth-Sun distance.
Historical origin. Astronomical unit was not the invention of a single named person; it developed through the process described above.
Understanding the Centimeter
Centimeter (cm) measures distance. A centimeter is one-hundredth of a meter. It is classified as a SI derived (metric prefix) unit.
Where it's used: Standard small-length unit worldwide except the US
Uses of the Centimeter today
- Everyday small-object and body measurement (height, clothing sizes) outside the US
- Construction and manufacturing tolerances internationally
History of the Centimeter
The centimeter follows directly from the meter via the 'centi-' SI prefix (10⁻²), introduced with the metric system in the 1790s.
Historical origin. Centimeter was not the invention of a single named person; it developed through the process described above.
Astronomical unit — sources
- IAU Resolution B2 (2012) — Fixes the astronomical unit at exactly 149,597,870,700 meters.
Centimeter — sources
- BIPM SI Brochure — SI prefixes — Defines 'centi-' as the prefix for 10⁻².
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many centimeters are in 1 astronomical unit?
1 astronomical unit equals 1.495979e+13 centimeters, using the exact defined conversion factor rather than an estimate.
How do I convert astronomical unit to centimeter?
Multiply the astronomical unit value by 1.495979e+13. The converter above does this instantly to whatever precision you set.
How do I convert centimeter back to astronomical unit?
Use the reverse factor: 1 centimeter equals 6.684587e-14 astronomical units. You can also use the swap control in the converter above to flip the direction instantly.
What is a astronomical unit?
Astronomical unit (AU) measures distance. The astronomical unit is defined as exactly 149,597,870,700 meters, close to the average Earth-Sun distance. It is classified as a Non-SI unit accepted for use with SI (astronomical).
What is a centimeter?
Centimeter (cm) measures distance. A centimeter is one-hundredth of a meter. It is classified as a SI derived (metric prefix) unit.
Is the astronomical unit to centimeter conversion exact?
Yes. The astronomical unit is defined as exactly 149,597,870,700 meters, close to the average Earth-Sun distance. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
Where is the astronomical unit still used today?
Used internationally in astronomy for solar-system-scale distances.