A barn is a nuclear cross-section unit equal to 1e-28 square meters.
Barns to Square Petameters Converter — b to Pm2
Convert Barn (b) to Square Petameter (Pm2) using the exact conversion factor (1 barn = 1e-58 square petameter). See the formula, worked examples, and conversion table.
Barns to Square Petameters 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 / 1e+30.
Area uses the square meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Barns to Square Petameters
Comparing Barn and Square Petameter 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 petameters = barns × 1e-58
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 petameter equals 1e+30 base units, so dividing one by the other gives the direct barn-to-square petameter factor of 1e-58.
Simple example
1 b × 1e-58 = 1e-58 Pm2
1 barn = 1e-58 square petameters.
Real-world example
10 b × 1e-58 = 1e-57 Pm2
10 barns = 1e-57 square petameters.
Conversion table
| Barn (b) | Square Petameter (Pm2) |
|---|---|
| 1 b | 1e-58 Pm2 |
| 5 b | 5e-58 Pm2 |
| 10 b | 1e-57 Pm2 |
| 25 b | 2.5e-57 Pm2 |
| 50 b | 5e-57 Pm2 |
| 100 b | 1e-56 Pm2 |
Reverse conversion: Square Petameter to Barn
1e-58 Pm2 × 1e+58 = 1 b
1e-58 square petameters = 1 barns.
barns = square petameters × 1e+58
For a page dedicated to this direction, see Square Petameter to Barn.
Understanding the Barn (b)
A barn is a nuclear cross-section unit equal to 1e-28 square meters.
Understanding the Square Petameter (Pm2)
Square metric area unit.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many square petameters are in 1 barn?
1 barn equals 1e-58 square petameters, using the exact defined conversion factor rather than an estimate.
How do I convert barn to square petameter?
Multiply the barn value by 1e-58. The converter above does this instantly to whatever precision you set.
How do I convert square petameter back to barn?
Use the reverse factor: 1 square petameter equals 1e+58 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 petameter?
Square Petameter (Pm2) is a unit of area.
Is the barn to square petameter conversion exact?
Yes. Both barn and square petameter are defined by fixed standards rather than physical artifacts, so the factor of 1e-58 used above is exact to as many digits as you choose to display.