Convert Square Kilometer to Barn
Convert square kilometers to barns instantly. 1 square kilometer = 1e+34 barn — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Barn to Square Kilometer converter for the reverse conversion.
Units explained
Square Kilometer
A square kilometer is a metric unit of area equal to 1,000,000 m² (one million square meters), or 100 hectares. It is used for measuring large land areas, regional geography, and country-scale statistics.
Derived by squaring the kilometer (1000 m). The kilo- prefix comes from the Greek 'chilioi' (thousand).
Square kilometers express the area of cities, districts, lakes, forests, and entire countries. India's total area is approximately 3,287,263 km². 1 km² equals 100 hectares or about 247.105 acres.
Kilometer has been part of the metric system since 1795.
Barn
A barn is a scientific unit of area equal to exactly 10⁻²⁸ m² (100 fm²). It is used in nuclear and particle physics to express interaction cross-sections.
Named in 1942 at Purdue University by physicists working on the Manhattan Project. The name comes from the phrase 'big as a barn' — uranium nuclei have cross-sections this large, which physicists initially considered surprisingly large for nuclear targets.
Barns and their submultiples (millibarn, microbarn, nanobarn, picobarn, femtobarn) are the standard units for cross-section measurements in nuclear physics, high-energy physics, and accelerator experiments. The Higgs boson production cross-section at the LHC is in the picobarn range.
Named in 1942 during the Manhattan Project; adopted internationally in particle physics.
Square Kilometer to Barn conversion formula
The relationship between square kilometers and barns:
To convert square kilometers to barns, multiply the value in square kilometers by 1e+34. To reverse, multiply barns by 1e-34.
How to use this converter
Type a value into the calculator. The result in barns updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Barn to Square Kilometer converter for the reverse direction.
Step-by-step: convert square kilometers to barns
- Write down the value in square kilometers (km²).
- Multiply that value by the factor 1e+34.
- The product is the equivalent value in barns (b).
- To reverse, multiply the barn value by 1e-34.
Worked examples
Example 1 — Convert 1 km² to b:
1 × 1e+34 = 1e+34 b
Example 2 — Convert 100 km² to b:
100 × 1e+34 = 1e+36 b
Square Kilometer to Barn conversion table
Standard reference values for converting square kilometers to barns:
| Square Kilometer [km²] | Barn [b] |
|---|---|
| 0.01 | 1e+32 |
| 0.1 | 1e+33 |
| 1 | 1e+34 |
| 2 | 2e+34 |
| 3 | 3e+34 |
| 4 | 4e+34 |
| 5 | 5e+34 |
| 10 | 1e+35 |
| 20 | 2e+35 |
| 30 | 3e+35 |
| 40 | 4e+35 |
| 50 | 5e+35 |
| 100 | 1e+36 |
| 500 | 5e+36 |
| 1000 | 1e+37 |
Frequently asked questions
How many barns is 1 square kilometer?
How do I convert square kilometers to barns?
How do I convert barns back to square kilometers?
How many barns is 100 square kilometers?
Popular area unit conversions
Convert Square Kilometer to other area units
Show all Square Kilometer conversions
Metric / SI (15 units)
Imperial / US Customary (15 units)
US Survey (5 units)
Indian Subcontinent (16 units)
Other Regional (10 units)
Scientific / Physics (5 units)
Sources & references
Conversion factor (1 km² = 1e+34 b) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.