Convert Exameter to Meter
Convert exameters to meters instantly. 1 exameter = 1e+18 meter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Meter to Exameter converter for the reverse conversion.
Units explained
Exameter
An exameter is a metric unit of length equal to one quintillion meters (1×10¹⁸ m). It is among the largest defined SI prefix units of length and appears almost exclusively in astrophysical contexts.
The exameter uses the SI prefix exa- (from Greek hex, six, related to the exponent's powers-of-thousand grouping), adopted by the CGPM in 1975 to denote 10¹⁸.
Exameters could be used to express galactic-scale distances. One kiloparsec is approximately 30.9 Em. Astronomy generally uses parsecs, kiloparsecs, and megaparsecs instead.
SI prefix exa- adopted in 1975; the exameter has very limited practical use because galactic-scale astronomy has its own well-established unit system.
Meter
The meter is the SI base unit of length. Since 2019, the meter has been defined by fixing the numerical value of the speed of light in vacuum to exactly 299,792,458 meters per second. Every other SI length unit derives from the meter.
The meter was originally defined in 1793 by the French Academy of Sciences as one ten-millionth of the distance from the equator to the North Pole along a meridian through Paris. It has been redefined multiple times — by physical prototype, then by atomic transitions, and finally in 2019 by fundamental physical constants.
The meter is the international standard for length in science, engineering, construction, athletics, and everyday measurement in metric countries. It underpins definitions of area (m²), volume (m³), and most derived SI units.
Established 1793 in France; ratified internationally via the Metre Convention 1875; redefined in 1960, 1983, and most recently 2019 when the SI redefinition fixed it to the speed of light.
Exameter to Meter conversion formula
The relationship between exameters and meters:
To convert exameters to meters, multiply the value in exameters by 1e+18. To reverse, multiply meters by 1e-18.
How to use this converter
Type a value into the calculator. The result in meters updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Meter to Exameter converter for the reverse direction.
Step-by-step: convert exameters to meters
- Write down the value in exameters (Em).
- Multiply that value by the factor 1e+18.
- The product is the equivalent value in meters (m).
- To reverse, multiply the meter value by 1e-18.
Worked examples
Example 1 — Convert 1 Em to m:
1 × 1e+18 = 1e+18 m
Example 2 — Convert 100 Em to m:
100 × 1e+18 = 1e+20 m
Exameter to Meter conversion table
Standard reference values for converting exameters to meters:
| Exameter [Em] | Meter [m] |
|---|---|
| 0.01 | 1e+16 |
| 0.1 | 1e+17 |
| 1 | 1e+18 |
| 2 | 2e+18 |
| 3 | 3e+18 |
| 4 | 4e+18 |
| 5 | 5e+18 |
| 10 | 1e+19 |
| 20 | 2e+19 |
| 30 | 3e+19 |
| 40 | 4e+19 |
| 50 | 5e+19 |
| 100 | 1e+20 |
| 500 | 5e+20 |
| 1000 | 1e+21 |
Frequently asked questions
How many meters is 1 exameter?
How do I convert exameters to meters?
How do I convert meters back to exameters?
How many meters is 100 exameters?
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Sources & references
Conversion factor (1 Em = 1e+18 m) 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 Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.