Quick answer
Astronomical Unit Calculator: what it calculates
Astronomical Unit Calculator calculates converted astronomy distance from distance, from unit and to unit. The visible formula is 1 AU = 149,597,870,700 meters exactly.
Everyday Calculators
Astronomical Unit Calculator
Use this astronomical unit calculator to translate solar-system distances into everyday distance units without losing the AU reference.
Formula checked June 6, 2026Source note includedFree tool
Live converter
Astronomical units
Converted distance149,597,870.7
1 astronomical units to kilometers.
Astronomical units1 AU
149,597,870.7 kilometers.
Miles92,955,807.3 mi
149,597,870,700 meters.
AU reference
| Reference | Value |
|---|---|
| 1 AU | 149,597,870,700 m |
| 1 AU | 149,597,870.7 km |
| 1 AU | About 92,955,807.3 mi |
ResultConverted astronomy distance
InputsDistance, From unit, To unit
FormulaAstronomical unit formula
Formula
Astronomical unit formula
1 AU = 149,597,870,700 meters exactlyThe calculator uses the IAU fixed astronomical unit and then applies standard length conversions.
How to use
Steps
- Enter the distance value.
- Choose whether the input is in AU, kilometers, meters, or miles.
- Choose the target distance unit.
- Use the reference outputs to compare the same distance across common astronomy units.
Example
Sample calculation
Input1 AU
Kilometers149,597,870.7 km
MilesAbout 92,955,807.3 mi
Calculator use
Best for
- Use this astronomical unit calculator to translate solar-system distances into everyday distance units without losing the AU reference.
- Calculating astronomical unit formula with the method and assumptions visible.
- Comparing the output with the sample calculation and benchmark table before using it elsewhere.
- Quick everyday math with the result and formula in one place.
Before relying on it
Check first
- Using the converted astronomy distance without checking that distance, from unit and to unit match the same task and context.
- Ignoring that the calculator uses the IAU fixed astronomical unit and then applies standard length conversions.
- Skipping the source notes when the formula, benchmark, or warning depends on outside context.
- Mixing units, dates, or original values across the same calculation.
Details
What to know before using the result
These notes make the assumptions explicit, especially where the same search query can mean slightly different things.
AU basis149,597,870,700 m
The astronomical unit is a fixed conventional length used for solar-system distances.
Best useLarge distance comparison
AU keeps planetary-scale distances readable while kilometers and miles help with familiar comparisons.
PrecisionRound for communication
Keep only the significant figures your source distance supports.
Source notes
References used for this calculator
Benchmarks
How to read the result
The calculator is a decision aid, not a fixed rule. Use the output to compare scenarios and document your assumptions. Benchmark ranges are broad planning heuristics unless this page names a specific source for the range.
1 AU: 149,597,870.7 km.
Solar-system distance reference.
0.5 AU: 74,798,935.35 km.
Useful fractional-AU check.
1 AU: About 92.96 million miles.
Common U.S. customary comparison.
Calculator accuracy
Methodology and assumptions
The formula, inputs, example, and limitations are shown so the result is checkable, not just a number in a box.
Formula
1 AU = 149,597,870,700 meters exactly
Inputs used
Distance, From unit, To unit
Limitations
Everyday results are quick planning checks. Unit choices, rounding, labels, measurements, local prices, and real-world constraints can change the final decision.
Last reviewed
June 6, 2026
Cite this page
Toolkit Shelf. Astronomical Unit Calculator. Last reviewed June 6, 2026. https://toolkitshelf.com/tools/astronomical-unit-calculator
FAQ
Common questions
What is one astronomical unit?
One astronomical unit is exactly 149,597,870,700 meters by IAU definition.
Is an AU the exact Earth-Sun distance?
No. It is a fixed reference length. Earth's actual distance from the Sun varies through its orbit.
When should I use AU instead of kilometers?
Use AU when solar-system distances become too large to scan comfortably in kilometers or miles.
Why might the real-world result differ?
Match the result to the task type: shopping tools depend on the same unit and usable quantity, home-project tools depend on field measurements and waste, date/time tools depend on counting rules, and conversion tools depend on the unit system.
Should I round the result?
Round for readability after checking the formula and units. Keep more precision when the result feeds another calculation, and add a task-specific buffer only when shortage, waste, or timing risk matters.
Why might another calculator show a different output?
Different tools may use different rounding, assumptions, default rates, methods, formulas, or input timing. Compare the visible method and inputs before relying on the output.