Length · Unit Converter

Convert Dekameter to Megameter

Convert dekameters to megameters instantly. 1 dekameter = 1e-5 megameter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Megameter to Dekameter converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Length category 2 min read Published Last reviewed Updated

Units explained

Metric / SI

Dekameter

What is a dekameter?

A dekameter (also spelled decameter) is a metric unit of length equal to ten meters (10 m). It is one of the less commonly used SI prefix units and primarily appears in agricultural, surveying, and atmospheric contexts.

Origin of the dekameter

The dekameter was defined alongside the meter when France adopted the metric system in 1795, using the standard SI prefix deca- (from Greek deka, ten) to denote a multiplication by ten.

Where it is used

Dekameters are used in some European agricultural contexts (parcel sizes, field measurements), atmospheric science (cloud heights), and certain track and field events. Modern usage is uncommon outside specialised technical fields.

When and where it was developed

Adopted in 1795 in France; ratified through the Metre Convention of 1875; remains a recognised SI prefix unit although informally superseded by the more common meter and hectometer in everyday surveying.

Metric / SI

Megameter

What is a megameter?

A megameter is a metric unit of length equal to one million meters (1×10⁶ m, or 1,000 km). It is occasionally used in geophysics and astronomy when expressing planetary-scale distances in SI units.

Origin of the megameter

The megameter uses the SI prefix mega- (from Greek megas, great), adopted by the CGPM in 1960 to denote multiplication by one million.

Where it is used

Megameters appear in geophysics (Earth's mean radius is 6.371 Mm), planetary science, and large-scale civil engineering planning. The unit is less common than the kilometer for everyday geographic distances.

When and where it was developed

SI prefix mega- adopted in 1960; the megameter is the standard SI prefix unit for distances comparable to planetary radii.

Dekameter to Megameter conversion formula

The relationship between dekameters and megameters:

1 dam = 1e-5 Mm
1 Mm = 100000 dam

To convert dekameters to megameters, multiply the value in dekameters by 1e-5. To reverse, multiply megameters by 100000.

How to use this converter

Type a value into the calculator. The result in megameters updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Megameter to Dekameter converter for the reverse direction.

Step-by-step: convert dekameters to megameters

  1. Write down the value in dekameters (dam).
  2. Multiply that value by the factor 1e-5.
  3. The product is the equivalent value in megameters (Mm).
  4. To reverse, multiply the megameter value by 100000.

Worked examples

Example 1 — Convert 1 dam to Mm:
1 × 1e-5 = 1e-5 Mm

Example 2 — Convert 100 dam to Mm:
100 × 1e-5 = 0.001 Mm

Dekameter to Megameter conversion table

Standard reference values for converting dekameters to megameters:

Dekameter [dam]Megameter [Mm]
0.011e-7
0.11e-6
11e-5
22e-5
33e-5
44e-5
55e-5
100.0001
200.0002
300.0003
400.0004
500.0005
1000.001
5000.005
10000.01

Frequently asked questions

How many megameters is 1 dekameter?
1 dekameter equals 1e-5 megameter.
How do I convert dekameters to megameters?
Multiply the value in dekameters by 1e-5 to get megameters.
How do I convert megameters back to dekameters?
Multiply the value in megameters by 100000, or use the Megameter to Dekameter converter.
How many megameters is 100 dekameters?
100 dekameters equals 0.001 megameters, because 100 × 1e-5 = 0.001.

Convert Dekameter to other length units

Show all Dekameter conversions

Sources & references

Conversion factor (1 dam = 1e-5 Mm) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.