How do I convert mm to a fraction of an inch?

Divide by 25.4 to get decimal inches, then round to the nearest 1/16, 1/32 or 1/64. For example, 10 mm ≈ 0.3937 in ≈ 25/64".

How do I convert mm to cm?

Divide millimeters by 10. For example, 100 mm = 10 cm = 3.937 inches.

Precision Tool

Millimeters to Inches,
instantly.

A live converter with fractions, feet, an interactive ruler, and printable charts. Built for engineers, makers and craftsmen.1 in = 25.4 mm.

Browse full chart Fraction reference →

Millimeters

Inches

Fraction

Feet & inches

Formula

25.4 ÷ 25.4

Tip: click or drag on the ruler to set the value.

Live conversion chart

Real-time visualization of mm to inches across the scale.

See full chart →

Ready when you are

Convert any value in one tap.

Type a number, drag the ruler, or flip units — you get precise decimals, fractions and feet instantly.

Try the converter Open interactive ruler

Browse all values

Tap any value for details

Millimeters

0.1 mm 0.2 mm 0.25 mm 0.3 mm 0.4 mm 0.5 mm 0.6 mm 0.7 mm 0.75 mm 0.8 mm 0.9 mm 1 mm 1.1 mm 1.2 mm 1.25 mm 1.3 mm 1.4 mm 1.5 mm 1.6 mm 1.7 mm 1.75 mm 1.8 mm 1.9 mm 2 mm 2.1 mm 2.2 mm 2.25 mm 2.3 mm 2.4 mm 2.5 mm 2.54 mm 2.6 mm 2.7 mm 2.8 mm 2.9 mm 3 mm 3.1 mm 3.175 mm 3.18 mm 3.2 mm 3.3 mm 3.4 mm 3.5 mm 3.6 mm 3.8 mm 3.9 mm 4 mm 4.2 mm 4.3 mm 4.5 mm 4.6 mm 4.7 mm 4.75 mm 4.8 mm 5 mm 5.2 mm 5.3 mm 5.5 mm 5.6 mm 5.8 mm 6 mm 6.2 mm 6.3 mm 6.35 mm 6.4 mm 6.5 mm 6.6 mm 6.8 mm 7 mm 7.3 mm 7.5 mm 7.6 mm 7.8 mm 7.9 mm 8 mm 8.1 mm 8.3 mm 8.4 mm 8.5 mm 8.8 mm 9 mm 9.5 mm 9.53 mm 10 mm 10.2 mm 10.5 mm 11 mm 11.5 mm 12 mm 12.4 mm 12.5 mm 12.7 mm 13 mm 13.5 mm 14 mm 14.5 mm 15 mm 15.5 mm 15.9 mm 16 mm 16.5 mm 17 mm 17.3 mm 17.5 mm 18 mm 18.5 mm 19 mm 19.05 mm 19.1 mm 19.5 mm 20 mm 20.5 mm 21 mm 21.5 mm 22 mm 22.2 mm 22.5 mm 23 mm 24 mm 24.5 mm 25 mm 25.4 mm 25.5 mm 26 mm 27 mm 28 mm 28.5 mm 28.6 mm 29 mm 30 mm 30.5 mm 31 mm 31.75 mm 31.8 mm 32 mm 33 mm 34 mm 35 mm 36 mm 37 mm 37.5 mm 38 mm 38.1 mm 38.5 mm 39 mm 40 mm 41 mm 42 mm 43 mm 44 mm 44.5 mm 45 mm 46 mm 47 mm 48 mm 49 mm 50 mm 50.8 mm 51 mm 52 mm 53 mm 54 mm 55 mm 56 mm 57 mm 58 mm 59 mm 60 mm 61 mm 62 mm 62.5 mm 63 mm 63.5 mm 64 mm 65 mm 66 mm 67 mm 68 mm 69 mm 70 mm 71 mm 72 mm 73 mm 74 mm 75 mm 76 mm 76.2 mm 77 mm 78 mm 79 mm 80 mm 81 mm 82 mm 83 mm 84 mm 85 mm 86 mm 87 mm 88 mm 88.9 mm 89 mm 90 mm 91 mm 92 mm 93 mm 94 mm 95 mm 96 mm 97 mm 98 mm 99 mm 100 mm 101 mm 101.6 mm 102 mm 103 mm 104 mm 105 mm 106 mm 107 mm 108 mm 109 mm 110 mm 111 mm 112 mm 113 mm 114 mm 114.3 mm 115 mm 116 mm 117 mm 118 mm 119 mm 120 mm 121 mm 122 mm 123 mm 124 mm 125 mm 126 mm 127 mm 128 mm 129 mm 130 mm 131 mm 132 mm 133 mm 134 mm 135 mm 136 mm 137 mm 138 mm 139 mm 139.7 mm 140 mm 141 mm 142 mm 143 mm 144 mm 145 mm 146 mm 147 mm 148 mm 149 mm 150 mm 152 mm 152.4 mm 153 mm 154 mm 155 mm 156 mm 157 mm 158 mm 160 mm 162 mm 163 mm 164 mm 165 mm 165.1 mm 166 mm 167 mm 168 mm 169 mm 170 mm 171 mm 172 mm 173 mm 174 mm 175 mm 176 mm 177 mm 178 mm 180 mm 183 mm 184 mm 185 mm 186 mm 188 mm 190 mm 192 mm 193 mm 195 mm 196 mm 197 mm 198 mm 199 mm 200 mm 202 mm 203 mm 203.2 mm 204 mm 205 mm 206 mm 208 mm 210 mm 211 mm 212 mm 215 mm 216 mm 217 mm 218 mm 219 mm 220 mm 222 mm 224 mm 225 mm 228 mm 229 mm 230 mm 231 mm 233 mm 234 mm 235 mm 240 mm 241 mm 242 mm 244 mm 245 mm 250 mm 252 mm 253 mm 254 mm 255 mm 256 mm 260 mm 262 mm 263 mm 264 mm 265 mm 266 mm 267 mm 268 mm 270 mm 272 mm 273 mm 275 mm 277 mm 279 mm 280 mm 285 mm 288 mm 290 mm 291 mm 292 mm 293 mm 294 mm 295 mm 296 mm 297 mm 300 mm 302 mm 303 mm 304 mm 305 mm 310 mm 312 mm 315 mm 316 mm 320 mm 321 mm 322 mm 324 mm 325 mm 328 mm 330 mm 332 mm 335 mm 340 mm 341 mm 344 mm 345 mm 350 mm 352 mm 355 mm 356 mm 357 mm 360 mm 365 mm 370 mm 375 mm 380 mm 381 mm 385 mm 389 mm 390 mm 392 mm 400 mm 405 mm 406 mm 410 mm 415 mm 420 mm 425 mm 430 mm 432 mm 434 mm 435 mm 440 mm 445 mm 450 mm 457 mm 458 mm 460 mm 465 mm 470 mm 475 mm 480 mm 490 mm 495 mm 500 mm 508 mm 510 mm 515 mm 520 mm 530 mm 540 mm 545 mm 550 mm 560 mm 570 mm 575 mm 580 mm 590 mm 594 mm 600 mm 610 mm 620 mm 622 mm 630 mm 635 mm 640 mm 650 mm 660 mm 670 mm 675 mm 680 mm 690 mm 700 mm 710 mm 720 mm 730 mm 740 mm 750 mm 760 mm 762 mm 770 mm 780 mm 790 mm 800 mm 810 mm 820 mm 830 mm 850 mm 860 mm 870 mm 880 mm 890 mm 900 mm 910 mm 914 mm 915 mm 920 mm 930 mm 940 mm 950 mm 960 mm 990 mm 1000 mm 1020 mm 1040 mm 1050 mm 1070 mm 1080 mm 1100 mm 1120 mm 1134 mm 1150 mm 1180 mm 1200 mm 1219 mm 1220 mm 1250 mm 1270 mm 1300 mm 1350 mm 1400 mm 1450 mm 1500 mm 1550 mm 1600 mm 1650 mm 1700 mm 1722 mm 1800 mm 1900 mm 2000 mm 2100 mm 2200 mm 2300 mm 2400 mm 2500 mm 2600 mm 3000 mm 3200 mm 4000 mm 4200 mm 4200 mm 4800 mm 5000 mm

Inches

1/16"1/8"3/16"3/16"1/4"3/8"3/8"7/16"1/2"9/16"5/8"5/8"11/16"3/4"13/16"7/8"7/8"15/16"1"1 1/8"1 3/16"1 1/4"1 5/16"1 3/8"1 3/8"1 1/2"1 9/16"1 5/8"1 5/8"1 5/8"1 11/16"1 11/16"1 3/4"1 3/4"1 13/16"1 7/8"1 7/8"1 15/16"1.97"2"2 1/16"2 1/8"2 1/8"2 3/16"2 1/4"2 1/4"2 5/16"2 3/8"2 3/8"2 3/8"2 7/16"2 1/2"2 1/2"2 9/16"2 5/8"2 5/8"2 11/16"2 3/4"2 3/4"2 13/16"2 7/8"2 7/8"2 15/16"3"3 1/16"3 1/8"3 1/8"3 1/8"3 1/4"3 1/4"3 5/16"3 3/8"3 3/8"3 1/2"3 1/2"3 5/8"3 3/4"3 3/4"3 7/8"4"4 1/8"4 1/8"4 1/4"4 1/4"4 3/8"4 1/2"4 1/2"4 5/8"4 3/4"4 3/4"5"5 1/8"5 1/8"5 1/4"5 1/4"5 3/8"5 1/2"5 1/2"5 5/8"5 3/4"5 3/4"5 7/8"6"6 1/8"6 1/4"6 1/4"6 5/16"6 1/2"6 1/2"6 3/4"6 3/4"6 7/8"7"7 1/4"7 1/2"7 3/4"8"8 1/4"8 1/2"8 3/4"9"9 1/4"9 1/2"9 3/4"10"10 1/4"10 1/2"11"11 1/4"11 1/2"11 3/4"12"12 1/4"12 1/2"12 3/4"13"13 1/2"13 3/4"14"14 1/2"15"15 1/2"15 3/4"16"16 1/2"17"18"19"20"21"22"23"24"24 1/2"25"26"27"28"29"30"31"32"33"34"35"36"40"48"60"

Frequently asked questions

How do I convert mm to inches?

Divide the millimeter value by 25.4. For example, 100 mm ÷ 25.4 = 3.937 inches.

How do I convert inches to mm?

Multiply inches by 25.4. For example, 2 in × 25.4 = 50.8 mm. See the inches to mm page.

How many mm are in one inch?

Exactly 25.4 mm. A foot (12 inches) is 304.8 mm.

How do I write mm to inches as a fraction?

Convert to decimal inches, then round to the nearest 1/16, 1/32 or 1/64. The fraction chart lists every value.

Conversion tools

Inches to mm

Convert the other way

MM to inches chart

Full conversion table

Millimeters to Inches,
instantly.

Live conversion chart

Popular mm → inches

Popular inches → mm

Convert any value in one tap.

Browse all values

Millimeters

Inches

Frequently asked questions

How do I convert mm to inches?

How do I convert inches to mm?

How many mm are in one inch?

How do I write mm to inches as a fraction?

Conversion tools

Millimeters to Inches, instantly.

Live conversion chart

Popular mm → inches

Popular inches → mm

Convert any value in one tap.

Browse all values

Millimeters

Inches

Frequently asked questions

How do I convert mm to inches?

How do I convert inches to mm?

How many mm are in one inch?

How do I write mm to inches as a fraction?

Conversion tools

Millimeters to Inches,
instantly.