Length · Unit Converter

Convert Terameter to Attometer

Convert terameters to attometers instantly. 1 terameter = 1e+30 attometer — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Attometer to Terameter 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

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.

Metric / SI

Attometer

What is a attometer?

An attometer is a metric unit of length equal to one quintillionth of a meter (1×10⁻¹⁸ m). It is among the smallest length units in the SI system and is used almost exclusively in particle physics and theoretical work involving sub-nuclear dimensions.

Origin of the attometer

The attometer was defined using the SI prefix atto- (from Danish atten, meaning eighteen), adopted by the Conférence Générale des Poids et Mesures (CGPM) in 1964 to denote one quintillionth (10⁻¹⁸).

Where it is used

Attometers appear in particle physics literature when describing distances comparable to or smaller than nuclear dimensions, including the range of weak nuclear interactions and theoretical Planck-scale ratios. They are rarely encountered outside specialised scientific work.

When and where it was developed

SI prefix atto- adopted in 1964; the attometer became the standard unit for sub-femtometer measurements in high-energy physics from the late 20th century onward.

Terameter to Attometer conversion formula

The relationship between terameters and attometers:

1 Tm = 1e+30 am
1 am = 1e-30 Tm

To convert terameters to attometers, multiply the value in terameters by 1e+30. To reverse, multiply attometers by 1e-30.

How to use this converter

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

Step-by-step: convert terameters to attometers

  1. Write down the value in terameters (Tm).
  2. Multiply that value by the factor 1e+30.
  3. The product is the equivalent value in attometers (am).
  4. To reverse, multiply the attometer value by 1e-30.

Worked examples

Example 1 — Convert 1 Tm to am:
1 × 1e+30 = 1e+30 am

Example 2 — Convert 100 Tm to am:
100 × 1e+30 = 1e+32 am

Terameter to Attometer conversion table

Standard reference values for converting terameters to attometers:

Terameter [Tm]Attometer [am]
0.011e+28
0.11e+29
11e+30
22e+30
33e+30
44e+30
55e+30
101e+31
202e+31
303e+31
404e+31
505e+31
1001e+32
5005e+32
10001e+33

Frequently asked questions

How many attometers is 1 terameter?
1 terameter equals 1e+30 attometer.
How do I convert terameters to attometers?
Multiply the value in terameters by 1e+30 to get attometers.
How do I convert attometers back to terameters?
Multiply the value in attometers by 1e-30, or use the Attometer to Terameter converter.
How many attometers is 100 terameters?
100 terameters equals 1e+32 attometers, because 100 × 1e+30 = 1e+32.

Convert Terameter to other length units

Show all Terameter conversions

Sources & references

Conversion factor (1 Tm = 1e+30 am) verified against the following authoritative sources:

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