Дюймовый размер обозначается дробью и означает количество долей дюйма (1 дюйм (inch)= 25,4 мм), где вверху дроби (числителе) стоит часть количества, а внизу дроби (знаменателе) – количество долей дюйма. К примеру, 1/2" – одна вторая дюйма, 7/8" – семь восьмых дюйма и т.д. Дюймовая размерность в основном применяется на крепеже деталей и узлов механизмов автомобилей американского производства.
| дюйм = мм | дюйм = мм | дюйм = мм | дюйм = мм | дюйм = мм |
| 1/32 = 0.7938 | 1-1/32 = 26.1938 | 2-1/32 = 51.5938 | 3-1/32 = 76.9938 | 4-1/32 = 102.3938 |
| 1/16 = 1.5875 | 1-1/16 = 26.9875 | 2-1/16 = 52.3875 | 3-1/16 = 77.7875 | 4-1/16 = 103.1875 |
| 3/32 = 2.3812 | 1-3/32 = 27.7812 | 2-3/32 = 53.1812 | 3-3/32 = 78.5812 | 4-3/32 = 103.9812 |
| 1/8 = 3.1750 | 1-1/8 = 28.5750 | 2-1/8 = 53.9750 | 3-1/8 = 79.3750 | 4-1/8 = 104.7750 |
| 5/32 = 3.9688 | 1-5/32 = 29.3688 | 2-5/32 = 54.7688 | 3-5/32 = 80.1688 | 4-5/32 = 105.5688 |
| 3/16 = 4.7625 | 1-3/16 = 30.1625 | 2-3/16 = 55.5625 | 3-3/16 = 80.9625 | 4-3/16 = 106.3625 |
| 7/32 = 5.5562 | 1-7/32 = 30.9562 | 2-7/32 = 56.3562 | 3-7/32 = 81.7562 | 4-7/32 = 107.1562 |
| 1/4 = 6.3500 | 1-1/4 = 31.7500 | 2-1/4 = 57.1500 | 3-1/4 = 82.5500 | 4-1/4 = 107.9500 |
| 9/32 = 7.1438 | 1-9/32 = 32.5438 | 2-9/32 = 57.9438 | 3-9/32 = 83.3438 | 4-9/32 = 108.7438 |
| 5/16 = 7.9375 | 1-5/16 = 33.3375 | 2-5/16 = 58.7375 | 3-5/16 = 84.1375 | 4-5/16 = 109.5375 |
| 11/32 = 8.7312 | 1-11/32 = 34.1312 | 2-11/32 = 59.5312 | 3-11/32 = 84.9312 | 4-11/32 = 110.3312 |
| 3/8 = 9.5250 | 1-3/8 = 34.9250 | 2-3/8 = 60.3250 | 3-3/8 = 85.7250 | 4-3/8 = 111.1250 |
| 13/32 = 10.3188 | 1-13/32 = 35.7188 | 2-13/32 = 61.1188 | 3-13/32 = 86.5188 | 4-13/32 = 111.9188 |
| 7/16 = 11.1125 | 1-7/16 = 36.5125 | 2-7/16 = 61.9125 | 3-7/16 = 87.3125 | 4-7/16 = 112.7125 |
| 15/32 = 11.9062 | 1-15/32 = 37.3062 | 2-15/32 = 62.7062 | 3-15/32 = 88.1062 | 4-15/32 = 113.5062 |
| 1/2 = 12.7000 | 1-1/2 = 38.1000 | 2-1/2 = 63.5000 | 3-1/2 = 88.9000 | 4-1/2 = 114.3000 |
| 17/32 = 13.4938 | 1-17/32 = 38.8938 | 2-17/32 = 64.2938 | 3-17/32 = 89.6938 | 4-17/32 = 115.0938 |
| 9/16 = 14.2875 | 1-9/16 = 39.6875 | 2-9/16 = 65.0875 | 3-9/16 = 90.4875 | 4-9/16 = 115.8875 |
| 19/32 = 15.0812 | 1-19/32 = 40.4812 | 2-19/32 = 65.8812 | 3-19/32 = 91.2812 | 4-19/32 = 116.6812 |
| 5/8 = 15.8750 | 1-5/8 = 41.2750 | 2-5/8 = 66.6750 | 3-5/8 = 92.0750 | 4-5/8 = 117.4750 |
| 21/32 = 16.6688 | 1-21/32 = 42.0688 | 2-21/32 = 67.4688 | 3-21/32 = 92.8688 | 4-21/32 = 118.2688 |
| 11/16 = 17.4625 | 1-11/16 = 42.8625 | 2-11/16 = 68.2625 | 3-11/16 = 93.6625 | 4-11/16 = 119.0625 |
| 23/32 = 18.2562 | 1-23/32 = 43.6562 | 2-23/32 = 69.0562 | 3-23/32 = 94.4562 | 4-23/32 = 119.8562 |
| 3/4 = 19.0500 | 1-3/4 = 44.4500 | 2-3/4 = 69.8500 | 3-3/4 = 95.2500 | 4-3/4 = 120.4500 |
| 25/32 = 19.8438 | 1-25/32 = 45.2438 | 2-25/32 = 70.6438 | 3-25/32 = 96.0438 | 4-25/32 = 121.4438 |
| 13/16 = 20.6375 | 1-13/16 = 46.0375 | 2-13/16 = 71.4375 | 3-13/16 = 96.8375 | 4-13/16 = 122.2375 |
| 27/32 = 21.4312 | 1-27/32 = 46.8312 | 2-27/32 = 72.2312 | 3-27/32 = 97.6312 | 4-27/32 = 123.0312 |
| 7/8 = 22.2250 | 1-7/8 = 47.6250 | 2-7/8 = 73.0250 | 3-7/8 = 98.4250 | 4-7/8 = 123.8250 |
| 29/32 = 23.0188 | 1-29/32 = 48.4188 | 2-29/32 = 73.8188 | 3-29/32 = 99.2188 | 4-29/32 = 124.6188 |
| 15/16 = 23.8125 | 1-15/16 = 49.2125 | 2-15/16 = 74.6125 | 3-15/16 = 100.0125 | 4-15/16 = 125.4125 |
| 31/32 = 24.6062 | 1-31/32 = 50.0062 | 2-31/32 = 75.4062 | 3-31/32 = 100.8062 | 4-31/32 = 126.2062 |
| 1 = 25.4000 | 2 = 50.8000 | 3 = 76.2000 | 4 = 101.6000 | 5 = 127.0000 |
Для удобства определения метрических и дюймовых торцевых головок, производитель King Tony обозначает их разными цветами.
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| Метрическая торцевая головка | Дюймовая торцевая головка |