| square kilometer | 1 km2 | 2 km2 | 3 km2 | 4 km2 | 5 km2 | 6 km2 | 7 km2 | 8 km2 | 9 km2 | 10 km2 | 11 km2 | 12 km2 | 13 km2 | 14 km2 | 15 km2 | 16 km2 | 17 km2 | 18 km2 | 19 km2 | 20 km2 | 21 km2 | 22 km2 | 23 km2 | 24 km2 | 25 km2 | 26 km2 | 27 km2 | 28 km2 | 29 km2 | 30 km2 | 31 km2 | 32 km2 | 33 km2 | 34 km2 | 35 km2 | 36 km2 | 37 km2 | 38 km2 | 39 km2 | 40 km2 | 41 km2 | 42 km2 | 43 km2 | 44 km2 | 45 km2 | 46 km2 | 47 km2 | 48 km2 | 49 km2 | 50 km2 | 51 km2 | 52 km2 | 53 km2 | 54 km2 | 55 km2 | 56 km2 | 57 km2 | 58 km2 | 59 km2 | 60 km2 | 61 km2 | 62 km2 | 63 km2 | 64 km2 | 65 km2 | 66 km2 | 67 km2 | 68 km2 | 69 km2 | 70 km2 | 71 km2 | 72 km2 | 73 km2 | 74 km2 | 75 km2 | 76 km2 | 77 km2 | 78 km2 | 79 km2 | 80 km2 | 81 km2 | 82 km2 | 83 km2 | 84 km2 | 85 km2 | 86 km2 | 87 km2 | 88 km2 | 89 km2 | 90 km2 | 91 km2 | 92 km2 | 93 km2 | 94 km2 | 95 km2 | 96 km2 | 97 km2 | 98 km2 | 99 km2 | 100 km2 |
| barn | 1.0 × 1034 b | 2.0 × 1034 b | 3.0 × 1034 b | 4.0 × 1034 b | 5.0 × 1034 b | 6.0 × 1034 b | 7.0 × 1034 b | 8.0 × 1034 b | 9.0 × 1034 b | 1.0 × 1035 b | 1.1 × 1035 b | 1.2 × 1035 b | 1.3 × 1035 b | 1.4 × 1035 b | 1.5 × 1035 b | 1.6 × 1035 b | 1.7 × 1035 b | 1.8 × 1035 b | 1.9 × 1035 b | 2.0 × 1035 b | 2.1 × 1035 b | 2.2 × 1035 b | 2.3 × 1035 b | 2.4 × 1035 b | 2.5 × 1035 b | 2.6 × 1035 b | 2.7 × 1035 b | 2.8 × 1035 b | 2.9 × 1035 b | 3.0 × 1035 b | 3.1 × 1035 b | 3.2 × 1035 b | 3.3 × 1035 b | 3.4 × 1035 b | 3.5 × 1035 b | 3.6 × 1035 b | 3.7 × 1035 b | 3.8 × 1035 b | 3.9 × 1035 b | 4.0 × 1035 b | 4.1 × 1035 b | 4.2 × 1035 b | 4.3 × 1035 b | 4.4 × 1035 b | 4.5 × 1035 b | 4.6 × 1035 b | 4.7 × 1035 b | 4.8 × 1035 b | 4.9 × 1035 b | 5.0 × 1035 b | 5.1 × 1035 b | 5.2 × 1035 b | 5.3 × 1035 b | 5.4 × 1035 b | 5.5 × 1035 b | 5.6 × 1035 b | 5.7 × 1035 b | 5.8 × 1035 b | 5.9 × 1035 b | 6.0 × 1035 b | 6.1 × 1035 b | 6.2 × 1035 b | 6.3 × 1035 b | 6.4 × 1035 b | 6.5 × 1035 b | 6.6 × 1035 b | 6.7 × 1035 b | 6.8 × 1035 b | 6.9 × 1035 b | 7.0 × 1035 b | 7.1 × 1035 b | 7.2 × 1035 b | 7.3 × 1035 b | 7.4 × 1035 b | 7.5 × 1035 b | 7.6 × 1035 b | 7.7 × 1035 b | 7.8 × 1035 b | 7.9 × 1035 b | 8.0 × 1035 b | 8.1 × 1035 b | 8.2 × 1035 b | 8.3 × 1035 b | 8.4 × 1035 b | 8.5 × 1035 b | 8.6 × 1035 b | 8.7 × 1035 b | 8.8 × 1035 b | 8.9 × 1035 b | 9.0 × 1035 b | 9.1 × 1035 b | 9.2 × 1035 b | 9.3 × 1035 b | 9.4 × 1035 b | 9.5 × 1035 b | 9.6 × 1035 b | 9.7 × 1035 b | 9.8 × 1035 b | 9.9 × 1035 b | 1.0 × 1036 b |
Square kilometre (International spelling as used by the International Bureau of Weights and Measures) or square kilometer (American spelling), symbol km2, is a multiple of the square metre, the SI unit of area or surface area.
| 1 square kilometers = 1.0E+34 barns | 6 square kilometers = 6.0E+34 barns |
| 2 square kilometers = 2.0E+34 barns | 7 square kilometers = 7.0E+34 barns |
| 3 square kilometers = 3.0E+34 barns | 8 square kilometers = 8.0E+34 barns |
| 4 square kilometers = 4.0E+34 barns | 9 square kilometers = 9.0E+34 barns |
| 5 square kilometers = 5.0E+34 barns | 10 square kilometers = 1.0E+35 barns |
A barn (symbol: b) is a unit of area equal to 10−28 m2 (100 fm2). Originally used in nuclear physics for expressing the cross sectional area of nuclei and nuclear reactions, today it is also used in all fields of high-energy physics to express the cross sections of any scattering process, and is best understood as a measure of the probability of interaction between small particles.
| 1 barns = 1.0E-34 square kilometers | 6 barns = 6.0E-34 square kilometers |
| 2 barns = 2.0E-34 square kilometers | 7 barns = 7.0E-34 square kilometers |
| 3 barns = 3.0E-34 square kilometers | 8 barns = 8.0E-34 square kilometers |
| 4 barns = 4.0E-34 square kilometers | 9 barns = 9.0E-34 square kilometers |
| 5 barns = 5.0E-34 square kilometers | 10 barns = 1.0E-33 square kilometers |
| 1 square kilometers = 1.0 × 1034 barns |
| 1 barns = 1.0 × 10-34 square kilometers |