Reckoning / Measure / Fractions and decimals
Measure · exact
Fractions of an inch
Rulers divide the inch by halves down to sixty-fourths; drawings and machines use decimals and millimetres. Every 64th of an inch is a decimal that ends, and since the inch is exactly 25.4 mm, so is its value in millimetres.
Ruler
All 64ths
| Fraction | Inch | Millimetre |
|---|---|---|
| 1/64 | 0.015 625 | 0.396 875 |
| 1/32 | 0.031 25 | 0.793 75 |
| 3/64 | 0.046 875 | 1.190 625 |
| 1/16 | 0.062 5 | 1.587 5 |
| 5/64 | 0.078 125 | 1.984 375 |
| 3/32 | 0.093 75 | 2.381 25 |
| 7/64 | 0.109 375 | 2.778 125 |
| 1/8 | 0.125 | 3.175 |
| 9/64 | 0.140 625 | 3.571 875 |
| 5/32 | 0.156 25 | 3.968 75 |
| 11/64 | 0.171 875 | 4.365 625 |
| 3/16 | 0.187 5 | 4.762 5 |
| 13/64 | 0.203 125 | 5.159 375 |
| 7/32 | 0.218 75 | 5.556 25 |
| 15/64 | 0.234 375 | 5.953 125 |
| 1/4 | 0.25 | 6.35 |
| 17/64 | 0.265 625 | 6.746 875 |
| 9/32 | 0.281 25 | 7.143 75 |
| 19/64 | 0.296 875 | 7.540 625 |
| 5/16 | 0.312 5 | 7.937 5 |
| 21/64 | 0.328 125 | 8.334 375 |
| 11/32 | 0.343 75 | 8.731 25 |
| 23/64 | 0.359 375 | 9.128 125 |
| 3/8 | 0.375 | 9.525 |
| 25/64 | 0.390 625 | 9.921 875 |
| 13/32 | 0.406 25 | 10.318 75 |
| 27/64 | 0.421 875 | 10.715 625 |
| 7/16 | 0.437 5 | 11.112 5 |
| 29/64 | 0.453 125 | 11.509 375 |
| 15/32 | 0.468 75 | 11.906 25 |
| 31/64 | 0.484 375 | 12.303 125 |
| 1/2 | 0.5 | 12.7 |
| 33/64 | 0.515 625 | 13.096 875 |
| 17/32 | 0.531 25 | 13.493 75 |
| 35/64 | 0.546 875 | 13.890 625 |
| 9/16 | 0.562 5 | 14.287 5 |
| 37/64 | 0.578 125 | 14.684 375 |
| 19/32 | 0.593 75 | 15.081 25 |
| 39/64 | 0.609 375 | 15.478 125 |
| 5/8 | 0.625 | 15.875 |
| 41/64 | 0.640 625 | 16.271 875 |
| 21/32 | 0.656 25 | 16.668 75 |
| 43/64 | 0.671 875 | 17.065 625 |
| 11/16 | 0.687 5 | 17.462 5 |
| 45/64 | 0.703 125 | 17.859 375 |
| 23/32 | 0.718 75 | 18.256 25 |
| 47/64 | 0.734 375 | 18.653 125 |
| 3/4 | 0.75 | 19.05 |
| 49/64 | 0.765 625 | 19.446 875 |
| 25/32 | 0.781 25 | 19.843 75 |
| 51/64 | 0.796 875 | 20.240 625 |
| 13/16 | 0.812 5 | 20.637 5 |
| 53/64 | 0.828 125 | 21.034 375 |
| 27/32 | 0.843 75 | 21.431 25 |
| 55/64 | 0.859 375 | 21.828 125 |
| 7/8 | 0.875 | 22.225 |
| 57/64 | 0.890 625 | 22.621 875 |
| 29/32 | 0.906 25 | 23.018 75 |
| 59/64 | 0.921 875 | 23.415 625 |
| 15/16 | 0.937 5 | 23.812 5 |
| 61/64 | 0.953 125 | 24.209 375 |
| 31/32 | 0.968 75 | 24.606 25 |
| 63/64 | 0.984 375 | 25.003 125 |
Inches as decimals of a foot
Surveyors and builders often work in decimal feet. Twelfths do not end as decimals, so these are rounded.
| Inches | Foot |
|---|---|
| 1/4 in | 0.020 833 3… ft |
| 1/2 in | 0.041 666 7… ft |
| 3/4 in | 0.062 5 ft |
| 1 in | 0.083 333 3… ft |
| 1 1/4 in | 0.104 167… ft |
| 1 1/2 in | 0.125 ft |
| 1 3/4 in | 0.145 833… ft |
| 2 in | 0.166 667… ft |
| 2 1/4 in | 0.187 5 ft |
| 2 1/2 in | 0.208 333… ft |
| 2 3/4 in | 0.229 167… ft |
| 3 in | 0.25 ft |
| 3 1/4 in | 0.270 833… ft |
| 3 1/2 in | 0.291 667… ft |
| 3 3/4 in | 0.312 5 ft |
| 4 in | 0.333 333… ft |
| 4 1/4 in | 0.354 167… ft |
| 4 1/2 in | 0.375 ft |
| 4 3/4 in | 0.395 833… ft |
| 5 in | 0.416 667… ft |
| 5 1/4 in | 0.437 5 ft |
| 5 1/2 in | 0.458 333… ft |
| 5 3/4 in | 0.479 167… ft |
| 6 in | 0.5 ft |
| 6 1/4 in | 0.520 833… ft |
| 6 1/2 in | 0.541 667… ft |
| 6 3/4 in | 0.562 5 ft |
| 7 in | 0.583 333… ft |
| 7 1/4 in | 0.604 167… ft |
| 7 1/2 in | 0.625 ft |
| 7 3/4 in | 0.645 833… ft |
| 8 in | 0.666 667… ft |
| 8 1/4 in | 0.687 5 ft |
| 8 1/2 in | 0.708 333… ft |
| 8 3/4 in | 0.729 167… ft |
| 9 in | 0.75 ft |
| 9 1/4 in | 0.770 833… ft |
| 9 1/2 in | 0.791 667… ft |
| 9 3/4 in | 0.812 5 ft |
| 10 in | 0.833 333… ft |
| 10 1/4 in | 0.854 167… ft |
| 10 1/2 in | 0.875 ft |
| 10 3/4 in | 0.895 833… ft |
| 11 in | 0.916 667… ft |
| 11 1/4 in | 0.937 5 ft |
| 11 1/2 in | 0.958 333… ft |
| 11 3/4 in | 0.979 167… ft |