Cubic metric volume unit.
Cubic Kilometers to Cubic Gigameters Converter — km3 to Gm3
Convert Cubic Kilometer (km3) to Cubic Gigameter (Gm3) using the exact conversion factor (1 cubic kilometer = 1e-18 cubic gigameter). See the formula, worked examples, and conversion table.
Cubic Kilometers to Cubic Gigameters converter
Converter
Volume Converter
Convert metric, US customary, imperial, cooking, dry, and industrial volume units.
Context values
Some unit families need one extra value for a physically accurate result.
Cubic metric volume unit.
Result = input x 1e+9 / 1e+27.
Volume uses the cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Cubic Kilometers to Cubic Gigameters
Cubic Kilometer and Cubic Gigameter appear side by side at fuel pumps and on beverage labels, since the US measures liquids in gallons while most of the world uses liters. Both are cubic metric volume unit units.
Formula
cubic gigameters = cubic kilometers × 1e-18
This factor comes from each unit's defined relationship to the category's base unit: 1 cubic kilometer equals 1000000000 base units, and 1 cubic gigameter equals 1e+27 base units, so dividing one by the other gives the direct cubic kilometer-to-cubic gigameter factor of 1e-18.
Simple example
1 km3 × 1e-18 = 1e-18 Gm3
1 cubic kilometer = 1e-18 cubic gigameters.
Real-world example
10 km3 × 1e-18 = 1e-17 Gm3
10 cubic kilometers = 1e-17 cubic gigameters.
Conversion table
| Cubic Kilometer (km3) | Cubic Gigameter (Gm3) |
|---|---|
| 1 km3 | 1e-18 Gm3 |
| 5 km3 | 5e-18 Gm3 |
| 10 km3 | 1e-17 Gm3 |
| 25 km3 | 2.5e-17 Gm3 |
| 50 km3 | 5e-17 Gm3 |
| 100 km3 | 1e-16 Gm3 |
Reverse conversion: Cubic Gigameter to Cubic Kilometer
1e-18 Gm3 × 1e+18 = 1 km3
1e-18 cubic gigameters = 1 cubic kilometers.
cubic kilometers = cubic gigameters × 1e+18
For a page dedicated to this direction, see Cubic Gigameter to Cubic Kilometer.
Understanding the Cubic Kilometer (km3)
Cubic metric volume unit.
Understanding the Cubic Gigameter (Gm3)
Cubic metric volume unit.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many cubic gigameters are in 1 cubic kilometer?
1 cubic kilometer equals 1e-18 cubic gigameters, using the exact defined conversion factor rather than an estimate.
How do I convert cubic kilometer to cubic gigameter?
Multiply the cubic kilometer value by 1e-18. The converter above does this instantly to whatever precision you set.
How do I convert cubic gigameter back to cubic kilometer?
Use the reverse factor: 1 cubic gigameter equals 1e+18 cubic kilometers. You can also use the swap control in the converter above to flip the direction instantly.
What is a cubic kilometer?
Cubic Kilometer (km3) is a unit of volume.
What is a cubic gigameter?
Cubic Gigameter (Gm3) is a unit of volume.
Is the cubic kilometer to cubic gigameter conversion exact?
Yes. Both cubic kilometer and cubic gigameter are defined by fixed standards rather than physical artifacts, so the factor of 1e-18 used above is exact to as many digits as you choose to display.