Length · Unit Converter

Convert Gigameter to Terameter

Convert gigameters to terameters instantly. 1 gigameter = 0.001 terameter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Terameter to Gigameter 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

Gigameter

What is a gigameter?

A gigameter is a metric unit of length equal to one billion meters (1×10⁹ m). It is most often used in astronomy and astrophysics when expressing distances within the inner solar system.

Origin of the gigameter

The gigameter uses the SI prefix giga- (from Greek gigas, giant), adopted by the CGPM in 1960 to denote multiplication by one billion (10⁹).

Where it is used

Gigameters are used to express distances such as the Sun's diameter (~1.39 Gm), the Earth–Moon distance (~0.384 Gm), and similar inner-solar-system scales. Astronomical units and light-seconds are also common for these distances.

When and where it was developed

SI prefix giga- adopted in 1960; the gigameter became standard in astronomy for sub-AU distances by the late 20th century.

Metric / SI

Terameter

What is a terameter?

A terameter is a metric unit of length equal to one trillion meters (1×10¹² m). It is rare in everyday use but appears in astronomy when expressing solar-system-scale distances in SI units.

Origin of the terameter

The terameter uses the SI prefix tera- (from Greek teras, monster), adopted by the CGPM in 1960 to denote multiplication by one trillion (10¹²).

Where it is used

Terameters are occasionally used in astronomy to express distances on the order of Earth–Sun (~0.15 Tm or 1 AU) and outer-planet distances. The astronomical unit (AU) and light-hour are more common in practice.

When and where it was developed

SI prefix tera- adopted in 1960; the terameter is the standard SI prefix unit for distances comparable to inter-planetary scales but is less common than the AU in working astronomy.

Gigameter to Terameter conversion formula

The relationship between gigameters and terameters:

1 Gm = 0.001 Tm
1 Tm = 1000 Gm

To convert gigameters to terameters, multiply the value in gigameters by 0.001. To reverse, multiply terameters by 1000.

How to use this converter

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

Step-by-step: convert gigameters to terameters

  1. Write down the value in gigameters (Gm).
  2. Multiply that value by the factor 0.001.
  3. The product is the equivalent value in terameters (Tm).
  4. To reverse, multiply the terameter value by 1000.

Worked examples

Example 1 — Convert 1 Gm to Tm:
1 × 0.001 = 0.001 Tm

Example 2 — Convert 100 Gm to Tm:
100 × 0.001 = 0.1 Tm

Gigameter to Terameter conversion table

Standard reference values for converting gigameters to terameters:

Gigameter [Gm]Terameter [Tm]
0.011e-5
0.10.0001
10.001
20.002
30.003
40.004
50.005
100.01
200.02
300.03
400.04
500.05
1000.1
5000.5
10001

Frequently asked questions

How many terameters is 1 gigameter?
1 gigameter equals 0.001 terameter.
How do I convert gigameters to terameters?
Multiply the value in gigameters by 0.001 to get terameters.
How do I convert terameters back to gigameters?
Multiply the value in terameters by 1000, or use the Terameter to Gigameter converter.
How many terameters is 100 gigameters?
100 gigameters equals 0.1 terameters, because 100 × 0.001 = 0.1.

Convert Gigameter to other length units

Show all Gigameter conversions

Sources & references

Conversion factor (1 Gm = 0.001 Tm) verified against the following authoritative sources:

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