Square metric area unit.
Square Femtometers to Barns Converter — fm2 to b
Convert Square Femtometer (fm2) to Barn (b) using the exact conversion factor (1 square femtometer = 0.01 barn). See the formula, worked examples, and conversion table.
Square Femtometers to Barns converter
Converter
Area Converter
Convert land, construction, mapping, survey, and scientific area units.
Context values
Some unit families need one extra value for a physically accurate result.
A barn is a nuclear cross-section unit equal to 1e-28 square meters.
Result = input x 1e-30 / 1e-28.
Area uses the square meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Square Femtometers to Barns
Comparing Square Femtometer and Barn is common in agriculture and real estate, where US land is typically measured in acres and most of the rest of the world uses hectares. Specifically: Square metric area unit, and a barn is a nuclear cross-section unit equal to 1e-28 square meters.
Formula
barns = square femtometers × 0.01
This factor comes from each unit's defined relationship to the category's base unit: 1 square femtometer equals 1e-30 base units, and 1 barn equals 1e-28 base units, so dividing one by the other gives the direct square femtometer-to-barn factor of 0.01.
Simple example
1 fm2 × 0.01 = 0.01 b
1 square femtometer = 0.01 barns.
Real-world example
10 fm2 × 0.01 = 0.1 b
10 square femtometers = 0.1 barns.
Conversion table
| Square Femtometer (fm2) | Barn (b) |
|---|---|
| 1 fm2 | 0.01 b |
| 5 fm2 | 0.05 b |
| 10 fm2 | 0.1 b |
| 25 fm2 | 0.25 b |
| 50 fm2 | 0.5 b |
| 100 fm2 | 1 b |
Reverse conversion: Barn to Square Femtometer
0.01 b × 100 = 1 fm2
0.01 barns = 1 square femtometers.
square femtometers = barns × 100
For a page dedicated to this direction, see Barn to Square Femtometer.
Understanding the Square Femtometer (fm2)
Square metric area unit.
Understanding the Barn (b)
A barn is a nuclear cross-section unit equal to 1e-28 square meters.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many barns are in 1 square femtometer?
1 square femtometer equals 0.01 barns, using the exact defined conversion factor rather than an estimate.
How do I convert square femtometer to barn?
Multiply the square femtometer value by 0.01. The converter above does this instantly to whatever precision you set.
How do I convert barn back to square femtometer?
Use the reverse factor: 1 barn equals 100 square femtometers. You can also use the swap control in the converter above to flip the direction instantly.
What is a square femtometer?
Square Femtometer (fm2) is a unit of area.
What is a barn?
Barn (b) is a unit of area.
Is the square femtometer to barn conversion exact?
Yes. Both square femtometer and barn are defined by fixed standards rather than physical artifacts, so the factor of 0.01 used above is exact to as many digits as you choose to display.