| kilometers per hour | 1 km/h | 2 km/h | 3 km/h | 4 km/h | 5 km/h | 6 km/h | 7 km/h | 8 km/h | 9 km/h | 10 km/h | 11 km/h | 12 km/h | 13 km/h | 14 km/h | 15 km/h | 16 km/h | 17 km/h | 18 km/h | 19 km/h | 20 km/h | 21 km/h | 22 km/h | 23 km/h | 24 km/h | 25 km/h | 26 km/h | 27 km/h | 28 km/h | 29 km/h | 30 km/h | 31 km/h | 32 km/h | 33 km/h | 34 km/h | 35 km/h | 36 km/h | 37 km/h | 38 km/h | 39 km/h | 40 km/h | 41 km/h | 42 km/h | 43 km/h | 44 km/h | 45 km/h | 46 km/h | 47 km/h | 48 km/h | 49 km/h | 50 km/h | 51 km/h | 52 km/h | 53 km/h | 54 km/h | 55 km/h | 56 km/h | 57 km/h | 58 km/h | 59 km/h | 60 km/h | 61 km/h | 62 km/h | 63 km/h | 64 km/h | 65 km/h | 66 km/h | 67 km/h | 68 km/h | 69 km/h | 70 km/h | 71 km/h | 72 km/h | 73 km/h | 74 km/h | 75 km/h | 76 km/h | 77 km/h | 78 km/h | 79 km/h | 80 km/h | 81 km/h | 82 km/h | 83 km/h | 84 km/h | 85 km/h | 86 km/h | 87 km/h | 88 km/h | 89 km/h | 90 km/h | 91 km/h | 92 km/h | 93 km/h | 94 km/h | 95 km/h | 96 km/h | 97 km/h | 98 km/h | 99 km/h | 100 km/h |
| speed of sound (68 °F) | 0.0008098 s | 0.0016197 s | 0.0024295 s | 0.0032394 s | 0.0040492 s | 0.0048591 s | 0.0056689 s | 0.0064788 s | 0.0072886 s | 0.0080985 s | 0.0089083 s | 0.0097182 s | 0.0105280 s | 0.0113379 s | 0.0121477 s | 0.0129576 s | 0.0137674 s | 0.0145773 s | 0.0153871 s | 0.0161970 s | 0.0170068 s | 0.0178167 s | 0.0186265 s | 0.0194363 s | 0.0202462 s | 0.0210560 s | 0.0218659 s | 0.0226757 s | 0.0234856 s | 0.0242954 s | 0.0251053 s | 0.0259151 s | 0.0267250 s | 0.0275348 s | 0.0283447 s | 0.0291545 s | 0.0299644 s | 0.0307742 s | 0.0315841 s | 0.0323939 s | 0.0332038 s | 0.0340136 s | 0.0348235 s | 0.0356333 s | 0.0364431 s | 0.0372530 s | 0.0380628 s | 0.0388727 s | 0.0396825 s | 0.0404924 s | 0.0413022 s | 0.0421121 s | 0.0429219 s | 0.0437318 s | 0.0445416 s | 0.0453515 s | 0.0461613 s | 0.0469712 s | 0.0477810 s | 0.0485909 s | 0.0494007 s | 0.0502106 s | 0.0510204 s | 0.0518303 s | 0.0526401 s | 0.0534500 s | 0.0542598 s | 0.0550696 s | 0.0558795 s | 0.0566893 s | 0.0574992 s | 0.0583090 s | 0.0591189 s | 0.0599287 s | 0.0607386 s | 0.0615484 s | 0.0623583 s | 0.0631681 s | 0.0639780 s | 0.0647878 s | 0.0655977 s | 0.0664075 s | 0.0672174 s | 0.0680272 s | 0.0688371 s | 0.0696469 s | 0.0704568 s | 0.0712666 s | 0.0720764 s | 0.0728863 s | 0.0736961 s | 0.0745060 s | 0.0753158 s | 0.0761257 s | 0.0769355 s | 0.0777454 s | 0.0785552 s | 0.0793651 s | 0.0801749 s | 0.0809848 s |
The kilometre per hour (American English: kilometer per hour) is a unit of speed, expressing the number of kilometres travelled in one hour.
| 1 kilometers per hour ≈ 0.00080984774862326 speed of sounds (68 °F) | 6 kilometers per hour ≈ 0.0048590864917396 speed of sounds (68 °F) |
| 2 kilometers per hour ≈ 0.0016196954972465 speed of sounds (68 °F) | 7 kilometers per hour ≈ 0.0056689342403628 speed of sounds (68 °F) |
| 3 kilometers per hour ≈ 0.0024295432458698 speed of sounds (68 °F) | 8 kilometers per hour ≈ 0.0064787819889861 speed of sounds (68 °F) |
| 4 kilometers per hour ≈ 0.003239390994493 speed of sounds (68 °F) | 9 kilometers per hour ≈ 0.0072886297376093 speed of sounds (68 °F) |
| 5 kilometers per hour ≈ 0.0040492387431163 speed of sounds (68 °F) | 10 kilometers per hour ≈ 0.0080984774862326 speed of sounds (68 °F) |
The speed of sound is the distance travelled per unit time by a sound wave as it propagates through an elastic medium. In dry air at 0 °C (32 °F), the speed of sound is 331.2 metres per second (1,087 ft/s; 1,192 km/h; 741 mph; 644 kn). At 20 °C (68 °F), the speed of sound is 343 metres per second (1,125 ft/s; 1,235 km/h; 767 mph; 667 kn), or a kilometre in 2.91 s or a mile in 4.69 s.
| 1 speed of sounds (68 °F) ≈ 1234.8 kilometers per hour | 6 speed of sounds (68 °F) ≈ 7408.8 kilometers per hour |
| 2 speed of sounds (68 °F) ≈ 2469.6 kilometers per hour | 7 speed of sounds (68 °F) ≈ 8643.6 kilometers per hour |
| 3 speed of sounds (68 °F) ≈ 3704.4 kilometers per hour | 8 speed of sounds (68 °F) ≈ 9878.4 kilometers per hour |
| 4 speed of sounds (68 °F) ≈ 4939.2 kilometers per hour | 9 speed of sounds (68 °F) ≈ 11113.2 kilometers per hour |
| 5 speed of sounds (68 °F) ≈ 6174 kilometers per hour | 10 speed of sounds (68 °F) ≈ 12348 kilometers per hour |
| 1 kilometers per hour ≈ 0.0008098 speed of sounds (68 °F) |
| 1 speed of sounds (68 °F) ≈ 1,234.8 kilometers per hour |