Length · Unit Converter

Convert Square Femtometer to Are

Convert square femtometers to ares instantly. 1 square femtometer = 1e-32 are — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Are to Square Femtometer 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

Square Femtometer

What is a square femtometer?

A square femtometer is a metric unit of area equal to 10⁻³⁰ m². It is used in nuclear and particle physics to describe interaction cross-sections at the nuclear scale.

Origin of the square femtometer

Derived by squaring the femtometer (10⁻¹⁵ m), historically known as the fermi after physicist Enrico Fermi.

Where it is used

Square femtometers are equivalent to 0.01 barn. They appear in particle physics literature comparing strong interaction cross-sections and hadron sizes.

When and where it was developed

Femtometer adopted into SI in 1964; the fermi nomenclature predates this from mid-20th century nuclear physics.

Metric / SI

Are

What is a are?

An are is a metric unit of area equal to 100 square meters. It is used in some European countries for land measurement, especially for smaller plots like vineyards and gardens.

Origin of the are

Introduced as part of the French metric system in 1795. The name comes from the Latin 'area' meaning surface or open ground.

Where it is used

Ares are still used in some European countries (especially Switzerland and France) for small-plot land measurement. In Switzerland, an are is a common unit for vineyard size. Most modern contexts prefer square meters or hectares.

When and where it was developed

Defined in 1795 in France as part of the original metric system.

Square Femtometer to Are conversion formula

The relationship between square femtometers and ares:

1 fm² = 1e-32 a
1 a = 1e+32 fm²

To convert square femtometers to ares, multiply the value in square femtometers by 1e-32. To reverse, multiply ares by 1e+32.

How to use this converter

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

Step-by-step: convert square femtometers to ares

  1. Write down the value in square femtometers (fm²).
  2. Multiply that value by the factor 1e-32.
  3. The product is the equivalent value in ares (a).
  4. To reverse, multiply the are value by 1e+32.

Worked examples

Example 1 — Convert 1 fm² to a:
1 × 1e-32 = 1e-32 a

Example 2 — Convert 100 fm² to a:
100 × 1e-32 = 1e-30 a

Real-world example — Wavelengths across the spectrum

Optical and atomic-scale phenomena are routinely cross-converted between sub-micron units. A photon of wavelength 800 square femtometers can be re-expressed in ares for direct comparison with another instrument's calibration data sheet.

800 fm² × 1e-32 = 8e-30 a

Real-world example — Molecular dimensions

The diameter of small molecular structures (around 2 square femtometers) is often converted into related sub-micron units when comparing measurements across different microscopy techniques or imaging modalities.

2 fm² × 1e-32 = 2e-32 a

Square Femtometer to Are conversion table

Standard reference values for converting square femtometers to ares:

Square Femtometer [fm²]Are [a]
0.011e-34
0.11e-33
11e-32
22e-32
33e-32
44e-32
55e-32
101e-31
202e-31
303e-31
404e-31
505e-31
1001e-30
5005e-30
10001e-29

Frequently asked questions

How many ares is 1 square femtometer?
1 square femtometer equals 1e-32 are.
How do I convert square femtometers to ares?
Multiply the value in square femtometers by 1e-32 to get ares.
How do I convert ares back to square femtometers?
Multiply the value in ares by 1e+32, or use the Are to Square Femtometer converter.
How many ares is 100 square femtometers?
100 square femtometers equals 1e-30 ares, because 100 × 1e-32 = 1e-30.

Convert Square Femtometer to other area units

Show all Square Femtometer conversions

Sources & references

Conversion factor (1 fm² = 1e-32 a) verified against the following authoritative sources:

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