Megameter is 1000000 meter units.
Megameters to Gigameters Converter — Mm to Gm
Convert Megameter (Mm) to Gigameter (Gm) using the exact conversion factor (1 megameter = 0.001 gigameter). See the formula, worked examples, and conversion table.
Megameters to Gigameters 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.
Gigameter is 1000000000 meter units.
Result = input x 1e+6 / 1e+9.
Length uses the meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Megameters to Gigameters
Megameter and Gigameter both measure length. Specifically: Megameter is 1000000 meter units, and gigameter is 1000000000 meter units.
Formula
gigameters = megameters × 0.001
This factor comes from each unit's defined relationship to the category's base unit: 1 megameter equals 1000000 base units, and 1 gigameter equals 1000000000 base units, so dividing one by the other gives the direct megameter-to-gigameter factor of 0.001.
Simple example
1 Mm × 0.001 = 0.001 Gm
1 megameter = 0.001 gigameters.
Real-world example
10 Mm × 0.001 = 0.01 Gm
10 megameters = 0.01 gigameters.
Conversion table
| Megameter (Mm) | Gigameter (Gm) |
|---|---|
| 1 Mm | 0.001 Gm |
| 5 Mm | 0.005 Gm |
| 10 Mm | 0.01 Gm |
| 21.0975 Mm | 0.0210975 Gm |
| 42.195 Mm | 0.042195 Gm |
| 100 Mm | 0.1 Gm |
Reverse conversion: Gigameter to Megameter
0.001 Gm × 1000 = 1 Mm
0.001 gigameters = 1 megameter.
megameters = gigameters × 1000
For a page dedicated to this direction, see Gigameter to Megameter.
Understanding the Megameter (Mm)
Megameter is 1000000 meter units.
Understanding the Gigameter (Gm)
Gigameter is 1000000000 meter units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many gigameters are in 1 megameter?
1 megameter equals 0.001 gigameters, using the exact defined conversion factor rather than an estimate.
How do I convert megameter to gigameter?
Multiply the megameter value by 0.001. The converter above does this instantly to whatever precision you set.
How do I convert gigameter back to megameter?
Use the reverse factor: 1 gigameter equals 1,000 megameters. You can also use the swap control in the converter above to flip the direction instantly.
What is a megameter?
Megameter (Mm) is a unit of length.
What is a gigameter?
Gigameter (Gm) is a unit of length.
Is the megameter to gigameter conversion exact?
Yes. Both megameter and gigameter are defined by fixed standards rather than physical artifacts, so the factor of 0.001 used above is exact to as many digits as you choose to display.