Convert Yard to A.u. of Length
Convert yards to a.u. of length instantly. 1 yard = 1.727966e+10 a.u. of length — use the live calculator, the exact formula, a conversion table and worked examples. Also check the A.u. of Length to Yard converter for the reverse conversion.
Units explained
Yard
A yard is an Imperial and US customary unit of length equal to 3 feet or exactly 0.9144 meters. It is used for medium distances, particularly in athletics and fabric/textile measurement.
The yard's origin is contested but traditionally attributed to the length from the tip of King Henry I's nose to the end of his outstretched thumb. It was standardized in English law from the medieval period and definitively fixed at 0.9144 m exactly by the 1959 International Yard and Pound Agreement.
Yards are used in American football (10 yards for a first down), golf course distances, fabric and carpet sales in the US, and short-distance running events. The UK uses yards informally and on road signs for short distances.
Standardized in English law from the Middle Ages; fixed at 0.9144 m exactly by the 1959 International Yard and Pound Agreement.
A.u. of Length
The atomic unit of length (a.u.) is equal to the Bohr radius — approximately 5.292×10⁻¹¹ m. Despite the abbreviation matching 'astronomical unit', this is a different unit used in atomic and molecular physics.
The atomic unit system was developed in the 1950s for quantum-chemistry calculations. The a.u. of length is defined as the Bohr radius (a₀), the most probable distance between the proton and electron in a hydrogen atom in its ground state.
The atomic unit of length is used throughout quantum chemistry, electronic-structure theory, and computational physics. Most quantum-mechanical equations simplify when expressed in atomic units rather than SI units.
Atomic unit system developed by Hartree in the 1920s; value fixed via CODATA 2018 determination of fundamental physical constants.
Yard to A.u. of Length conversion formula
The relationship between yards and a.u. of length:
To convert yards to a.u. of length, multiply the value in yards by 1.727966e+10. To reverse, multiply a.u. of length by 5.787152e-11.
How to use this converter
Type a value into the calculator. The result in a.u. of length updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the A.u. of Length to Yard converter for the reverse direction.
Step-by-step: convert yards to a.u. of length
- Write down the value in yards (yd).
- Multiply that value by the factor 1.727966e+10.
- The product is the equivalent value in a.u. of length (a.u.).
- To reverse, multiply the a.u. of length value by 5.787152e-11.
Worked examples
Example 1 — Convert 1 yd to a.u.:
1 × 1.727966e+10 = 1.727966e+10 a.u.
Example 2 — Convert 100 yd to a.u.:
100 × 1.727966e+10 = 1.727966e+12 a.u.
Real-world example — Human-scale to atomic dimensions
One yard equals one billion a.u. of length — the canonical metric conversion bridging everyday objects and atomic-scale features in physics, chemistry, and electronics.
1 yd × 1.727966e+10 = 1.727966e+10 a.u.
Real-world example — Meter to nanoscale
One yard equals one billion a.u. of length. Physics curricula use this conversion to teach orders of magnitude when introducing the electromagnetic spectrum.
1 yd × 1.727966e+10 = 1.727966e+10 a.u.
Yard to A.u. of Length conversion table
Standard reference values for converting yards to a.u. of length:
| Yard [yd] | A.u. of Length [a.u.] |
|---|---|
| 0.01 | 1.727966e+8 |
| 0.1 | 1.727966e+9 |
| 1 | 1.727966e+10 |
| 2 | 3.455931e+10 |
| 3 | 5.183897e+10 |
| 4 | 6.911862e+10 |
| 5 | 8.639828e+10 |
| 10 | 1.727966e+11 |
| 20 | 3.455931e+11 |
| 30 | 5.183897e+11 |
| 40 | 6.911862e+11 |
| 50 | 8.639828e+11 |
| 100 | 1.727966e+12 |
| 500 | 8.639828e+12 |
| 1000 | 1.727966e+13 |
Frequently asked questions
How many a.u. of length is 1 yard?
How do I convert yards to a.u. of length?
How do I convert a.u. of length back to yards?
How many a.u. of length is 100 yards?
Popular length unit conversions
Convert Yard to other length units
Show all Yard conversions
Metric / SI (18 units)
Imperial / US Customary (26 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 yd = 1.727966e+10 a.u.) 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.