A barn is a nuclear cross-section unit equal to 1e-28 square meters.
Barns to Square Decimeters Converter — b to dm2
Convert Barn (b) to Square Decimeter (dm2) using the exact conversion factor (1 barn = 1e-26 square decimeter). See the formula, worked examples, and conversion table.
Barns to Square Decimeters 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.
Square metric area unit.
Result = input x 1e-28 / 0.01.
Area uses the square meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Barns to Square Decimeters
Comparing Barn and Square Decimeter 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: A barn is a nuclear cross-section unit equal to 1e-28 square meters, and square metric area unit.
Formula
square decimeters = barns × 1e-26
This factor comes from each unit's defined relationship to the category's base unit: 1 barn equals 1e-28 base units, and 1 square decimeter equals 0.01 base units, so dividing one by the other gives the direct barn-to-square decimeter factor of 1e-26.
Simple example
1 b × 1e-26 = 1e-26 dm2
1 barn = 1e-26 square decimeters.
Real-world example
10 b × 1e-26 = 1e-25 dm2
10 barns = 1e-25 square decimeters.
Conversion table
| Barn (b) | Square Decimeter (dm2) |
|---|---|
| 1 b | 1e-26 dm2 |
| 5 b | 5e-26 dm2 |
| 10 b | 1e-25 dm2 |
| 25 b | 2.5e-25 dm2 |
| 50 b | 5e-25 dm2 |
| 100 b | 1e-24 dm2 |
Reverse conversion: Square Decimeter to Barn
1e-26 dm2 × 1e+26 = 1 b
1e-26 square decimeters = 1 barns.
barns = square decimeters × 1e+26
For a page dedicated to this direction, see Square Decimeter to Barn.
Understanding the Barn (b)
A barn is a nuclear cross-section unit equal to 1e-28 square meters.
Understanding the Square Decimeter (dm2)
Square metric area unit.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many square decimeters are in 1 barn?
1 barn equals 1e-26 square decimeters, using the exact defined conversion factor rather than an estimate.
How do I convert barn to square decimeter?
Multiply the barn value by 1e-26. The converter above does this instantly to whatever precision you set.
How do I convert square decimeter back to barn?
Use the reverse factor: 1 square decimeter equals 1e+26 barns. You can also use the swap control in the converter above to flip the direction instantly.
What is a barn?
Barn (b) is a unit of area.
What is a square decimeter?
Square Decimeter (dm2) is a unit of area.
Is the barn to square decimeter conversion exact?
Yes. Both barn and square decimeter are defined by fixed standards rather than physical artifacts, so the factor of 1e-26 used above is exact to as many digits as you choose to display.