here is, at least, a handy chart if you do need to convert simple fractions and decimaled US measurements to metric:
how very primitive we are measuring by body parts chopped in half and then half again and again……
| Fractional | Inches | Metric |
| 1/64 | .0156 | 0.396 |
| 1/32 | .0312 | 0.79387 |
| 3/64 | .0468 | 1.190 |
| 1/16 | .0625 | 1.587 |
| 5/64 | .0781 | 1.984 |
| 3/32 | .0937 | 2.381 |
| 7/64 | .1093 | 2.778 |
| 1/8 | .125 | 3.175 |
| 9/64 | .1406 | 3.571 |
| 5/32 | .1562 | 3.968 |
| 11/64 | .1718 | 4.365 |
| 3/16 | .1875 | 4.762 |
| 13/64 | .2031 | 5.159 |
| 7/32 | .2187 | 5.556 |
| 15/64 | .2343 | 5.953 |
| 1/4 | .250 | 6.350 |
| 17/64 | .2656 | 6.746 |
| 9/32 | .2812 | 7.143 |
| 19/64 | .2968 | 7.540 |
| 5/16 | .3125 | 7.937 |
| 21/64 | .3281 | 8.334 |
| 11/32 | .3437 | 8.731 |
| 23/64 | .3593 | 9.128 |
| 3/8 | .375 | 9.525 |
| 25/64 | .3906 | 9.921 |
| 13/32 | .4062 | 10.318 |
| 27/64 | .4218 | 10.715 |
| 7/16 | .4375 | 11.112 |
| 29/64 | .4531 | 11.509 |
| 15/32 | .4687 | 11.906 |
| 31/64 | .4843 | 12.303 |
| 1/2 | .500 | 12.700 |
| 33/64 | .5156 | 13.096 |
| 17/32 | .5312 | 13.493 |
| 35/64 | .5468 | 13.890 |
| 9/16 | .5625 | 14.287 |
| 37/64 | .5781 | 14.684 |
| 19/32 | .5937 | 15.081 |
| 39/64 | .6093 | 15.478 |
| 5/8 | .625 | 15.875 |
| 41/64 | .6406 | 16.271 |
| 21/32 | .6562 | 16.668 |
| 43/64 | .6718 | 17.065 |
| 11/16 | .6875 | 17.462 |
| 45/64 | .7031 | 17.859 |
| 23/32 | .7187 | 18.256 |
| 47/64 | .7343 | 18.653 |
| 3/4 | .750 | 19.050 |
| 49/64 | .7656 | 19.446 |
| 25/32 | .7812 | 19.843 |
| 51/64 | .7968 | 20.240 |
| 13/16 | .8125 | 20.637 |
| 53/64 | .8281 | 21.034 |
| 27/32 | .8437 | 21.431 |
| 55/64 | .8593 | 21.828 |
| 7/8 | .875 | 22.225 |
| 57/64 | .8906 | 22.621 |
| 29/32 | .9062 | 23.018 |
| 59/64 | .9218 | 23.415 |
| 15/16 | .9375 | 23.812 |
| 61/64 | .9531 | 24.209 |
| 31/32 | .9687 | 24.606 |
| 63/64 | .9843 | 25.003 |
| 1 | 1.000 | 25.400 |