英吋與毫米換算
英吋與毫米之間的換算方法和參考資料。
inchesconversion計算器
概述
英吋與毫米換算是工程、製造及營造領域最常見的計算之一。英吋是美制與英制的標準單位，毫米則廣泛用於全球公制設計。依 1959 年起採用的國際協議，1 英吋恰好等於 25.4 mm。
本頁提供換算公式、分數與小數英吋快速參考表，以及便於現場快速使用的互動式計算器。
關鍵公式
1 英吋等於多少毫米？
1 英吋恰好等於 25.4 毫米。
英吋換算為毫米：
毫米換算為英吋：
兩個換算關係都是精確值，不涉及任何捨入係數。
變量
| 符號 | 說明 | 單位 |
|---|---|---|
| 以英吋表示的長度 | in | |
| 以毫米表示的長度 | mm |
快速換算器
可進行雙向換算，所用常數皆為精確值。
英吋換算為毫米
毫米換算為英吋
分數英吋換算為毫米
以下列出機械加工、扣件及鑽頭組常用的分數英吋尺寸，以及對應的小數與公制值。
16 行
分數英吋 | 小數英吋 | 毫米 (mm) (mm) |
|---|---|---|
| 1/64 | 0.0156 | 0.3969 |
| 1/32 | 0.0313 | 0.7938 |
| 1/16 | 0.0625 | 1.5875 |
| 1/8 | 0.125 | 3.175 |
| 3/16 | 0.1875 | 4.7625 |
| 1/4 | 0.25 | 6.35 |
| 5/16 | 0.3125 | 7.9375 |
| 3/8 | 0.375 | 9.525 |
| 7/16 | 0.4375 | 11.1125 |
| 1/2 | 0.5 | 12.7 |
| 9/16 | 0.5625 | 14.2875 |
| 5/8 | 0.625 | 15.875 |
| 11/16 | 0.6875 | 17.4625 |
| 3/4 | 0.75 | 19.05 |
| 7/8 | 0.875 | 22.225 |
| 1 | 1 | 25.4 |
小數英吋換算為毫米
適用於游標卡尺的小數讀值及 CAD 尺寸標註。
16 行
英吋 (in) (in) | 毫米 (mm) (mm) |
|---|---|
| 0.1 | 2.54 |
| 0.2 | 5.08 |
| 0.3 | 7.62 |
| 0.4 | 10.16 |
| 0.5 | 12.7 |
| 0.6 | 15.24 |
| 0.7 | 17.78 |
| 0.8 | 20.32 |
| 0.9 | 22.86 |
| 1 | 25.4 |
| 2 | 50.8 |
| 5 | 127 |
| 10 | 254 |
| 12 | 304.8 |
| 24 | 609.6 |
| 36 | 914.4 |
毫米換算為英吋
mm 至英吋換算表
14 行
毫米 (mm) (mm) | 英吋 (in) (in) |
|---|---|
| 1 | 0.0394 |
| 2 | 0.0787 |
| 5 | 0.1969 |
| 10 | 0.3937 |
| 20 | 0.7874 |
| 25 | 0.9843 |
| 50 | 1.9685 |
| 75 | 2.9528 |
| 100 | 3.937 |
| 150 | 5.9055 |
| 200 | 7.874 |
| 300 | 11.811 |
| 500 | 19.685 |
| 1000 | 39.3701 |
英吋與毫米的關係
下圖顯示英吋與毫米之間的精確線性關係。由於換算係數固定，圖線是一條通過原點的直線。
英吋與毫米對照
還原的原始來源表格
以下表格由原始來源頁面還原，以保留完整的參考資料。
英吋至 mm 換算表的 pdf 格式版本。
下載並列印英吋至 mm 換算表。
分數及／或小數英吋與公制毫米互換
246 行
| . | 0.0039 | 0.1 |
| . | 0.0079 | 0.2 |
| . | 0.0118 | 0.3 |
| 1/64 | 0.0156 | 0.3969 |
| . | 0.0157 | 0.4 |
| . | 0.0197 | 0.5 |
| . | 0.0236 | 0.6 |
| . | 0.0276 | 0.7 |
| 1/32 | 0.0313 | 0.7938 |
| . | 0.0315 | 0.8 |
| . | 0.0354 | 0.9 |
| . | 0.0394 | 1 |
| . | 0.0433 | 1.1 |
| 3/64 | 0.0469 | 1.1906 |
| . | 0.0472 | 1.2 |
| . | 0.0512 | 1.3 |
| . | 0.0551 | 1.4 |
| . | 0.0591 | 1.5 |
| 1/16 | 0.0625 | 1.5875 |
| . | 0.063 | 1.6 |
| . | 0.0669 | 1.7 |
| . | 0.0709 | 1.8 |
| . | 0.0748 | 1.9 |
| 5/64 | 0.0781 | 1.9844 |
| . | 0.0787 | 2 |
| . | 0.0827 | 2.1 |
| . | 0.0866 | 2.2 |
| . | 0.0906 | 2.3 |
| 3/32 | 0.0938 | 2.3813 |
| . | 0.0945 | 2.4 |
| . | 0.0984 | 2.5 |
| 7/64 | 0.1094 | 2.7781 |
| . | 0.1181 | 3 |
| 1/8 | 0.125 | 3.175 |
| . | 0.1378 | 3.5 |
| 9/64 | 0.1406 | 3.5719 |
| 5/32 | 0.1563 | 3.9688 |
| . | 0.1575 | 4 |
| 11/64 | 0.1719 | 4.3656 |
| . | 0.1772 | 4.5 |
| 3/16 | 0.1875 | 4.7625 |
| . | 0.1969 | 5 |
| 13/64 | 0.2031 | 5.1594 |
| . | 0.2165 | 5.5 |
| 7/32 | 0.2188 | 5.5563 |
| 15/64 | 0.2344 | 5.9531 |
| . | 0.2362 | 6 |
| 1/4 | 0.25 | 6.35 |
| . | 0.2559 | 6.5 |
| 17/64 | 0.2656 | 6.7469 |
| . | 0.2756 | 7 |
| 9/32 | 0.2813 | 7.1438 |
| . | 0.2953 | 7.5 |
| 19/64 | 0.2969 | 7.5406 |
| 5/16 | 0.3125 | 7.9375 |
| . | 0.315 | 8 |
| 21/64 | 0.3281 | 8.3344 |
| . | 0.3346 | 8.5 |
| 11/32 | 0.3438 | 8.7313 |
| . | 0.3543 | 9 |
| 23/64 | 0.3594 | 9.1281 |
| . | 0.374 | 9.5 |
| 3/8 | 0.375 | 9.525 |
| 25/64 | 0.3906 | 9.9219 |
| . | 0.3937 | 10 |
| 13/32 | 0.4063 | 10.3188 |
| . | 0.4134 | 10.5 |
| 27/64 | 0.4219 | 10.7156 |
| . | 0.4331 | 11 |
| 7/16 | 0.4375 | 11.1125 |
| . | 0.4528 | 11.5 |
| 29/64 | 0.4531 | 11.5094 |
| 15/32 | 0.4688 | 11.9063 |
| . | 0.4724 | 12 |
| 31/64 | 0.4844 | 12.3031 |
| . | 0.4921 | 12.5 |
| 1/2 | 0.5 | 12.7 |
| . | 0.5118 | 13 |
| 33/64 | 0.5156 | 13.0969 |
| 17/32 | 0.5313 | 13.4938 |
| . | 0.5315 | 13.5 |
| 35/64 | 0.5469 | 13.8906 |
| . | 0.5512 | 14 |
| 9/16 | 0.5625 | 14.2875 |
| . | 0.5709 | 14.5 |
| 37/64 | 0.5781 | 14.6844 |
| . | 0.5906 | 15 |
| 19/32 | 0.5938 | 15.0813 |
| 39/64 | 0.6094 | 15.4781 |
| . | 0.6102 | 15.5 |
| 5/8 | 0.625 | 15.875 |
| . | 0.6299 | 16 |
| 41/64 | 0.6406 | 16.2719 |
| . | 0.6496 | 16.5 |
| 21/32 | 0.6563 | 16.6688 |
| . | 0.6693 | 17 |
| 43/64 | 0.6719 | 17.0656 |
| 11/16 | 0.6875 | 17.4625 |
| . | 0.689 | 17.5 |
| 45/64 | 0.7031 | 17.8594 |
| . | 0.7087 | 18 |
| 23/32 | 0.7188 | 18.2563 |
| . | 0.7283 | 18.5 |
| 47/64 | 0.7344 | 18.6531 |
| . | 0.748 | 19 |
| 3/4 | 0.75 | 19.05 |
| 49/64 | 0.7656 | 19.4469 |
| . | 0.7677 | 19.5 |
| 25/32 | 0.7813 | 19.8438 |
| . | 0.7874 | 20 |
| 51/64 | 0.7969 | 20.2406 |
| . | 0.8071 | 20.5 |
| 13/16 | 0.8125 | 20.6375 |
| . | 0.8268 | 21 |
| 53/64 | 0.8281 | 21.0344 |
| 27/32 | 0.8438 | 21.4313 |
| . | 0.8465 | 21.5 |
| 55/64 | 0.8594 | 21.8281 |
| . | 0.8661 | 22 |
| 7/8 | 0.875 | 22.225 |
| . | 0.8858 | 22.5 |
| 57/64 | 0.89063 | 22.6219 |
| . | 0.9055 | 23 |
| 29/32 | 0.90625 | 23.0188 |
| 59/64 | 0.92188 | 23.4156 |
| . | 0.9252 | 23.5 |
| 15/16 | 0.9375 | 23.8125 |
| . | 0.9449 | 24 |
| 61/64 | 0.95313 | 24.2094 |
| . | 0.9646 | 24.5 |
| 31/32 | 0.96875 | 24.6063 |
| . | 0.9843 | 25 |
| 63/64 | 0.98438 | 25.0031 |
| 1 | 1 | 25.4 |
| . | 1.0039 | 25.5 |
| . | 1.0236 | 26 |
| . | 1.0433 | 26.5 |
| . | 1.063 | 27 |
| . | 1.0827 | 27.5 |
| . | 1.1024 | 28 |
| . | 1.122 | 28.5 |
| . | 1.1417 | 29 |
| . | 1.1614 | 29.5 |
| . | 1.1811 | 30 |
| . | 1.2205 | 31 |
| 1 1/4 | 1.25 | 31.75 |
| . | 1.2598 | 32 |
| . | 1.2992 | 33 |
| . | 1.3386 | 34 |
| . | 1.378 | 35 |
| . | 1.4173 | 36 |
| . | 1.4567 | 37 |
| . | 1.4961 | 38 |
| 1 1/2 | 1.5 | 38.1 |
| . | 1.5354 | 39 |
| . | 1.5748 | 40 |
| . | 1.6142 | 41 |
| . | 1.6535 | 42 |
| . | 1.6929 | 43 |
| . | 1.7323 | 44 |
| 1 3/4 | 1.75 | 44.45 |
| . | 1.7717 | 45 |
| . | 1.811 | 46 |
| . | 1.8504 | 47 |
| . | 1.8898 | 48 |
| . | 1.9291 | 49 |
| . | 1.9685 | 50 |
| 2 | 2 | 50.8 |
| . | 2.0079 | 51 |
| . | 2.0472 | 52 |
| . | 2.0866 | 53 |
| . | 2.126 | 54 |
| . | 2.1654 | 55 |
| . | 2.2047 | 56 |
| . | 2.2441 | 57 |
| 2 1/4 | 2.25 | 57.15 |
| . | 2.2835 | 58 |
| . | 2.3228 | 59 |
| . | 2.3622 | 60 |
| . | 2.4016 | 61 |
| . | 2.4409 | 62 |
| . | 2.4803 | 63 |
| 2 1/2 | 2.5 | 63.5 |
| . | 2.5197 | 64 |
| . | 2.5591 | 65 |
| . | 2.5984 | 66 |
| . | 2.6378 | 67 |
| . | 2.6772 | 68 |
| . | 2.7165 | 69 |
| 2 3/4 | 2.75 | 69.85 |
| . | 2.7559 | 70 |
| . | 2.7953 | 71 |
| . | 2.8346 | 72 |
| . | 2.874 | 73 |
| . | 2.9134 | 74 |
| . | 2.9528 | 75 |
| . | 2.9921 | 76 |
| 3 | 3 | 76.2 |
| . | 3.0315 | 77 |
| . | 3.0709 | 78 |
| . | 3.1102 | 79 |
| . | 3.1496 | 80 |
| . | 3.189 | 81 |
| . | 3.2283 | 82 |
| . | 3.2677 | 83 |
| . | 3.3071 | 84 |
| . | 3.3465 | 85 |
| . | 3.3858 | 86 |
| . | 3.4252 | 87 |
| . | 3.4646 | 88 |
| 3 1/2 | 3.5 | 88.9 |
| . | 3.5039 | 89 |
| . | 3.5433 | 90 |
| . | 3.5827 | 91 |
| . | 3.622 | 92 |
| . | 3.6614 | 93 |
| . | 3.7008 | 94 |
| . | 3.7402 | 95 |
| . | 3.7795 | 96 |
| . | 3.8189 | 97 |
| . | 3.8583 | 98 |
| . | 3.8976 | 99 |
| . | 3.937 | 100 |
| 4 | 4 | 101.6 |
| . | 4.3307 | 110 |
| 4 1/2 | 4.5 | 114.3 |
| . | 4.7244 | 120 |
| 5 | 5 | 127 |
| . | 5.1181 | 130 |
| . | 5.5118 | 140 |
| . | 5.9055 | 150 |
| 6 | 6 | 152.4 |
| . | 6.2992 | 160 |
| . | 6.6929 | 170 |
| . | 7.0866 | 180 |
| . | 7.4803 | 190 |
| . | 7.874 | 200 |
| 8 | 8 | 203.2 |
| . | 9.8425 | 250 |
| 10 | 10 | 254 |
| 20 | 20 | 508 |
| 30 | 30 | 762 |
| 40 | 40 | 1016 |
| 60 | 60 | 1524 |
| 80 | 80 | 2032 |
| 100 | 100 | 2540 |
來源: engineeringtoolbox.com
小數英吋換算為 mm
11 行
英吋 (in) | 毫米 (mm) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 0.01 | 0.02 | 0.03 | 0.04 | 0.05 | 0.06 | 0.07 | 0.08 | 0.09 | — |
| 0 | 0 | 0.25 | 0.51 | 0.76 | 1.02 | 1.27 | 1.52 | 1.78 | 2.03 | 2.29 |
| 0.1 | 2.54 | 2.79 | 3.05 | 3.3 | 3.56 | 3.81 | 4.06 | 4.32 | 4.57 | 4.83 |
| 0.2 | 5.08 | 5.33 | 5.59 | 5.84 | 6.1 | 6.35 | 6.6 | 6.86 | 7.11 | 7.37 |
| 0.3 | 7.62 | 7.87 | 8.13 | 8.38 | 8.64 | 8.89 | 9.14 | 9.4 | 9.65 | 9.91 |
| 0.4 | 10.16 | 10.41 | 10.67 | 10.92 | 11.18 | 11.43 | 11.68 | 11.94 | 12.19 | 12.45 |
| 0.5 | 12.7 | 12.95 | 13.21 | 13.46 | 13.72 | 13.97 | 14.22 | 14.48 | 14.73 | 14.99 |
| 0.6 | 15.24 | 15.49 | 15.75 | 16 | 16.26 | 16.51 | 16.76 | 17.02 | 17.27 | 17.53 |
| 0.7 | 17.78 | 18.03 | 18.29 | 18.54 | 18.8 | 19.05 | 19.3 | 19.56 | 19.81 | 20.07 |
| 0.8 | 20.32 | 20.57 | 20.83 | 21.08 | 21.34 | 21.59 | 21.84 | 22.1 | 22.35 | 22.61 |
| 0.9 | — | — | — | — | — | — | — | — | — | — |
mm 換算為小數英吋
102 行
毫米 (mm) | 英吋 (in) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | — |
| 0 | 0 | 0.0394 | 0.0787 | 0.118 | 0.157 | 0.197 | 0.236 | 0.276 | 0.315 | 0.354 |
| 10 | 0.394 | 0.433 | 0.472 | 0.512 | 0.551 | 0.591 | 0.63 | 0.669 | 0.709 | 0.748 |
| 20 | 0.787 | 0.827 | 0.866 | 0.906 | 0.945 | 0.984 | 1.02 | 1.06 | 1.1 | 1.14 |
| 30 | 1.18 | 1.22 | 1.26 | 1.3 | 1.34 | 1.38 | 1.42 | 1.46 | 1.5 | 1.54 |
| 40 | 1.57 | 1.61 | 1.65 | 1.69 | 1.73 | 1.77 | 1.81 | 1.85 | 1.89 | 1.93 |
| 50 | 1.97 | 2.01 | 2.05 | 2.09 | 2.13 | 2.17 | 2.2 | 2.24 | 2.28 | 2.32 |
| 60 | 2.36 | 2.4 | 2.44 | 2.48 | 2.52 | 2.56 | 2.6 | 2.64 | 2.68 | 2.72 |
| 70 | 2.76 | 2.8 | 2.83 | 2.87 | 2.91 | 2.95 | 2.99 | 3.03 | 3.07 | 3.11 |
| 80 | 3.15 | 3.19 | 3.23 | 3.27 | 3.31 | 3.35 | 3.39 | 3.43 | 3.46 | 3.5 |
| 90 | 3.54 | 3.58 | 3.62 | 3.66 | 3.7 | 3.74 | 3.78 | 3.82 | 3.86 | 3.9 |
| 100 | 3.94 | 3.98 | 4.02 | 4.06 | 4.09 | 4.13 | 4.17 | 4.21 | 4.25 | 4.29 |
| 110 | 4.33 | 4.37 | 4.41 | 4.45 | 4.49 | 4.53 | 4.57 | 4.61 | 4.65 | 4.69 |
| 120 | 4.72 | 4.76 | 4.8 | 4.84 | 4.88 | 4.92 | 4.96 | 5 | 5.04 | 5.08 |
| 130 | 5.12 | 5.16 | 5.2 | 5.24 | 5.28 | 5.31 | 5.35 | 5.39 | 5.43 | 5.47 |
| 140 | 5.51 | 5.55 | 5.59 | 5.63 | 5.67 | 5.71 | 5.75 | 5.79 | 5.83 | 5.87 |
| 150 | 5.91 | 5.94 | 5.98 | 6.02 | 6.06 | 6.1 | 6.14 | 6.18 | 6.22 | 6.26 |
| 160 | 6.3 | 6.34 | 6.38 | 6.42 | 6.46 | 6.5 | 6.54 | 6.57 | 6.61 | 6.65 |
| 170 | 6.69 | 6.73 | 6.77 | 6.81 | 6.85 | 6.89 | 6.93 | 6.97 | 7.01 | 7.05 |
| 180 | 7.09 | 7.13 | 7.17 | 7.2 | 7.24 | 7.28 | 7.32 | 7.36 | 7.4 | 7.44 |
| 190 | 7.48 | 7.52 | 7.56 | 7.6 | 7.64 | 7.68 | 7.72 | 7.76 | 7.8 | 7.83 |
| 200 | 7.87 | 7.91 | 7.95 | 7.99 | 8.03 | 8.07 | 8.11 | 8.15 | 8.19 | 8.23 |
| 210 | 8.27 | 8.31 | 8.35 | 8.39 | 8.43 | 8.46 | 8.5 | 8.54 | 8.58 | 8.62 |
| 220 | 8.66 | 8.7 | 8.74 | 8.78 | 8.82 | 8.86 | 8.9 | 8.94 | 8.98 | 9.02 |
| 230 | 9.06 | 9.09 | 9.13 | 9.17 | 9.21 | 9.25 | 9.29 | 9.33 | 9.37 | 9.41 |
| 240 | 9.45 | 9.49 | 9.53 | 9.57 | 9.61 | 9.65 | 9.69 | 9.72 | 9.76 | 9.8 |
| 250 | 9.84 | 9.88 | 9.92 | 9.96 | 10 | 10 | 10.1 | 10.1 | 10.2 | 10.2 |
| 260 | 10.2 | 10.3 | 10.3 | 10.4 | 10.4 | 10.4 | 10.5 | 10.5 | 10.6 | 10.6 |
| 270 | 10.6 | 10.7 | 10.7 | 10.7 | 10.8 | 10.8 | 10.9 | 10.9 | 10.9 | 11 |
| 280 | 11 | 11.1 | 11.1 | 11.1 | 11.2 | 11.2 | 11.3 | 11.3 | 11.3 | 11.4 |
| 290 | 11.4 | 11.5 | 11.5 | 11.5 | 11.6 | 11.6 | 11.7 | 11.7 | 11.7 | 11.8 |
| 300 | 11.8 | 11.9 | 11.9 | 11.9 | 12 | 12 | 12 | 12.1 | 12.1 | 12.2 |
| 310 | 12.2 | 12.2 | 12.3 | 12.3 | 12.4 | 12.4 | 12.4 | 12.5 | 12.5 | 12.6 |
| 320 | 12.6 | 12.6 | 12.7 | 12.7 | 12.8 | 12.8 | 12.8 | 12.9 | 12.9 | 13 |
| 330 | 13 | 13 | 13.1 | 13.1 | 13.1 | 13.2 | 13.2 | 13.3 | 13.3 | 13.3 |
| 340 | 13.4 | 13.4 | 13.5 | 13.5 | 13.5 | 13.6 | 13.6 | 13.7 | 13.7 | 13.7 |
| 350 | 13.8 | 13.8 | 13.9 | 13.9 | 13.9 | 14 | 14 | 14.1 | 14.1 | 14.1 |
| 360 | 14.2 | 14.2 | 14.3 | 14.3 | 14.3 | 14.4 | 14.4 | 14.4 | 14.5 | 14.5 |
| 370 | 14.6 | 14.6 | 14.6 | 14.7 | 14.7 | 14.8 | 14.8 | 14.8 | 14.9 | 14.9 |
| 380 | 15 | 15 | 15 | 15.1 | 15.1 | 15.2 | 15.2 | 15.2 | 15.3 | 15.3 |
| 390 | 15.4 | 15.4 | 15.4 | 15.5 | 15.5 | 15.6 | 15.6 | 15.6 | 15.7 | 15.7 |
| 400 | 15.7 | 15.8 | 15.8 | 15.9 | 15.9 | 15.9 | 16 | 16 | 16.1 | 16.1 |
| 410 | 16.1 | 16.2 | 16.2 | 16.3 | 16.3 | 16.3 | 16.4 | 16.4 | 16.5 | 16.5 |
| 420 | 16.5 | 16.6 | 16.6 | 16.7 | 16.7 | 16.7 | 16.8 | 16.8 | 16.9 | 16.9 |
| 430 | 16.9 | 17 | 17 | 17 | 17.1 | 17.1 | 17.2 | 17.2 | 17.2 | 17.3 |
| 440 | 17.3 | 17.4 | 17.4 | 17.4 | 17.5 | 17.5 | 17.6 | 17.6 | 17.6 | 17.7 |
| 450 | 17.7 | 17.8 | 17.8 | 17.8 | 17.9 | 17.9 | 18 | 18 | 18 | 18.1 |
| 460 | 18.1 | 18.1 | 18.2 | 18.2 | 18.3 | 18.3 | 18.3 | 18.4 | 18.4 | 18.5 |
| 470 | 18.5 | 18.5 | 18.6 | 18.6 | 18.7 | 18.7 | 18.7 | 18.8 | 18.8 | 18.9 |
| 480 | 18.9 | 18.9 | 19 | 19 | 19.1 | 19.1 | 19.1 | 19.2 | 19.2 | 19.3 |
| 490 | 19.3 | 19.3 | 19.4 | 19.4 | 19.4 | 19.5 | 19.5 | 19.6 | 19.6 | 19.6 |
| 500 | 19.7 | 19.7 | 19.8 | 19.8 | 19.8 | 19.9 | 19.9 | 20 | 20 | 20 |
| 510 | 20.1 | 20.1 | 20.2 | 20.2 | 20.2 | 20.3 | 20.3 | 20.4 | 20.4 | 20.4 |
| 520 | 20.5 | 20.5 | 20.6 | 20.6 | 20.6 | 20.7 | 20.7 | 20.7 | 20.8 | 20.8 |
| 530 | 20.9 | 20.9 | 20.9 | 21 | 21 | 21.1 | 21.1 | 21.1 | 21.2 | 21.2 |
| 540 | 21.3 | 21.3 | 21.3 | 21.4 | 21.4 | 21.5 | 21.5 | 21.5 | 21.6 | 21.6 |
| 550 | 21.7 | 21.7 | 21.7 | 21.8 | 21.8 | 21.9 | 21.9 | 21.9 | 22 | 22 |
| 560 | 22 | 22.1 | 22.1 | 22.2 | 22.2 | 22.2 | 22.3 | 22.3 | 22.4 | 22.4 |
| 570 | 22.4 | 22.5 | 22.5 | 22.6 | 22.6 | 22.6 | 22.7 | 22.7 | 22.8 | 22.8 |
| 580 | 22.8 | 22.9 | 22.9 | 23 | 23 | 23 | 23.1 | 23.1 | 23.1 | 23.2 |
| 590 | 23.2 | 23.3 | 23.3 | 23.3 | 23.4 | 23.4 | 23.5 | 23.5 | 23.5 | 23.6 |
| 600 | 23.6 | 23.7 | 23.7 | 23.7 | 23.8 | 23.8 | 23.9 | 23.9 | 23.9 | 24 |
| 610 | 24 | 24.1 | 24.1 | 24.1 | 24.2 | 24.2 | 24.3 | 24.3 | 24.3 | 24.4 |
| 620 | 24.4 | 24.4 | 24.5 | 24.5 | 24.6 | 24.6 | 24.6 | 24.7 | 24.7 | 24.8 |
| 630 | 24.8 | 24.8 | 24.9 | 24.9 | 25 | 25 | 25 | 25.1 | 25.1 | 25.2 |
| 640 | 25.2 | 25.2 | 25.3 | 25.3 | 25.4 | 25.4 | 25.4 | 25.5 | 25.5 | 25.6 |
| 650 | 25.6 | 25.6 | 25.7 | 25.7 | 25.7 | 25.8 | 25.8 | 25.9 | 25.9 | 25.9 |
| 660 | 26 | 26 | 26.1 | 26.1 | 26.1 | 26.2 | 26.2 | 26.3 | 26.3 | 26.3 |
| 670 | 26.4 | 26.4 | 26.5 | 26.5 | 26.5 | 26.6 | 26.6 | 26.7 | 26.7 | 26.7 |
| 680 | 26.8 | 26.8 | 26.9 | 26.9 | 26.9 | 27 | 27 | 27 | 27.1 | 27.1 |
| 690 | 27.2 | 27.2 | 27.2 | 27.3 | 27.3 | 27.4 | 27.4 | 27.4 | 27.5 | 27.5 |
| 700 | 27.6 | 27.6 | 27.6 | 27.7 | 27.7 | 27.8 | 27.8 | 27.8 | 27.9 | 27.9 |
| 710 | 28 | 28 | 28 | 28.1 | 28.1 | 28.1 | 28.2 | 28.2 | 28.3 | 28.3 |
| 720 | 28.3 | 28.4 | 28.4 | 28.5 | 28.5 | 28.5 | 28.6 | 28.6 | 28.7 | 28.7 |
| 730 | 28.7 | 28.8 | 28.8 | 28.9 | 28.9 | 28.9 | 29 | 29 | 29.1 | 29.1 |
| 740 | 29.1 | 29.2 | 29.2 | 29.3 | 29.3 | 29.3 | 29.4 | 29.4 | 29.4 | 29.5 |
| 750 | 29.5 | 29.6 | 29.6 | 29.6 | 29.7 | 29.7 | 29.8 | 29.8 | 29.8 | 29.9 |
| 760 | 29.9 | 30 | 30 | 30 | 30.1 | 30.1 | 30.2 | 30.2 | 30.2 | 30.3 |
| 770 | 30.3 | 30.4 | 30.4 | 30.4 | 30.5 | 30.5 | 30.6 | 30.6 | 30.6 | 30.7 |
| 780 | 30.7 | 30.7 | 30.8 | 30.8 | 30.9 | 30.9 | 30.9 | 31 | 31 | 31.1 |
| 790 | 31.1 | 31.1 | 31.2 | 31.2 | 31.3 | 31.3 | 31.3 | 31.4 | 31.4 | 31.5 |
| 800 | 31.5 | 31.5 | 31.6 | 31.6 | 31.7 | 31.7 | 31.7 | 31.8 | 31.8 | 31.9 |
| 810 | 31.9 | 31.9 | 32 | 32 | 32 | 32.1 | 32.1 | 32.2 | 32.2 | 32.2 |
| 820 | 32.3 | 32.3 | 32.4 | 32.4 | 32.4 | 32.5 | 32.5 | 32.6 | 32.6 | 32.6 |
| 830 | 32.7 | 32.7 | 32.8 | 32.8 | 32.8 | 32.9 | 32.9 | 33 | 33 | 33 |
| 840 | 33.1 | 33.1 | 33.1 | 33.2 | 33.2 | 33.3 | 33.3 | 33.3 | 33.4 | 33.4 |
| 850 | 33.5 | 33.5 | 33.5 | 33.6 | 33.6 | 33.7 | 33.7 | 33.7 | 33.8 | 33.8 |
| 860 | 33.9 | 33.9 | 33.9 | 34 | 34 | 34.1 | 34.1 | 34.1 | 34.2 | 34.2 |
| 870 | 34.3 | 34.3 | 34.3 | 34.4 | 34.4 | 34.4 | 34.5 | 34.5 | 34.6 | 34.6 |
| 880 | 34.6 | 34.7 | 34.7 | 34.8 | 34.8 | 34.8 | 34.9 | 34.9 | 35 | 35 |
| 890 | 35 | 35.1 | 35.1 | 35.2 | 35.2 | 35.2 | 35.3 | 35.3 | 35.4 | 35.4 |
| 900 | 35.4 | 35.5 | 35.5 | 35.6 | 35.6 | 35.6 | 35.7 | 35.7 | 35.7 | 35.8 |
| 910 | 35.8 | 35.9 | 35.9 | 35.9 | 36 | 36 | 36.1 | 36.1 | 36.1 | 36.2 |
| 920 | 36.2 | 36.3 | 36.3 | 36.3 | 36.4 | 36.4 | 36.5 | 36.5 | 36.5 | 36.6 |
| 930 | 36.6 | 36.7 | 36.7 | 36.7 | 36.8 | 36.8 | 36.9 | 36.9 | 36.9 | 37 |
| 940 | 37 | 37 | 37.1 | 37.1 | 37.2 | 37.2 | 37.2 | 37.3 | 37.3 | 37.4 |
| 950 | 37.4 | 37.4 | 37.5 | 37.5 | 37.6 | 37.6 | 37.6 | 37.7 | 37.7 | 37.8 |
| 960 | 37.8 | 37.8 | 37.9 | 37.9 | 38 | 38 | 38 | 38.1 | 38.1 | 38.1 |
| 970 | 38.2 | 38.2 | 38.3 | 38.3 | 38.3 | 38.4 | 38.4 | 38.5 | 38.5 | 38.5 |
| 980 | 38.6 | 38.6 | 38.7 | 38.7 | 38.7 | 38.8 | 38.8 | 38.9 | 38.9 | 38.9 |
| 990 | 39 | 39 | 39.1 | 39.1 | 39.1 | 39.2 | 39.2 | 39.3 | 39.3 | 39.3 |
| 1000 | 39.4 | 39.4 | 39.4 | 39.5 | 39.5 | 39.6 | 39.6 | 39.6 | 39.7 | 39.7 |
原始源圖
以下保留原始來源圖片，以免遺失視覺參考資料。若圖片含有圖表或表格資料，其擷取值會呈現在頁面的表格、計算器或互動式圖表中；其餘圖片則保留作為視覺來源參考。
工程要點
- 精確定義： 自 1959 年起，國際英吋定義為恰好 25.4 mm，任何工程計算都不需使用捨入值。
- 分數精度： 1/64 inch 等分數換算時可保留四位小數。對大多數現場加工而言，捨入至兩位小數（0.01 mm）即可。
- 公差累積： 在英制與公制間換算帶公差的尺寸時，務必分別換算公稱值及公差上下限；不要只換算公差帶。
- 常見混淆： 美國測量英尺（用於部分土地測量情境）與國際英尺略有差異。這不影響英吋與毫米的關係，但進行大尺度座標換算時可能造成影響。
- 鑽頭與扣件標準： 分數英吋鑽頭尺寸（從 1/64 至 1 inch，以 1/64 遞增）及號碼鑽尺寸（No. 1–80）由 ANSI B94.2 規定。公制對應尺寸不一定完全相符；關鍵孔配合應查閱交叉參考表。
- CAD 實務： 多數現代 CAD 軟體可顯示雙重尺寸。請將主要單位設為加工現場標準，並為國際協作者顯示次要單位。