| twip | 1 twp | 2 twp | 3 twp | 4 twp | 5 twp | 6 twp | 7 twp | 8 twp | 9 twp | 10 twp | 11 twp | 12 twp | 13 twp | 14 twp | 15 twp | 16 twp | 17 twp | 18 twp | 19 twp | 20 twp | 21 twp | 22 twp | 23 twp | 24 twp | 25 twp | 26 twp | 27 twp | 28 twp | 29 twp | 30 twp | 31 twp | 32 twp | 33 twp | 34 twp | 35 twp | 36 twp | 37 twp | 38 twp | 39 twp | 40 twp | 41 twp | 42 twp | 43 twp | 44 twp | 45 twp | 46 twp | 47 twp | 48 twp | 49 twp | 50 twp | 51 twp | 52 twp | 53 twp | 54 twp | 55 twp | 56 twp | 57 twp | 58 twp | 59 twp | 60 twp | 61 twp | 62 twp | 63 twp | 64 twp | 65 twp | 66 twp | 67 twp | 68 twp | 69 twp | 70 twp | 71 twp | 72 twp | 73 twp | 74 twp | 75 twp | 76 twp | 77 twp | 78 twp | 79 twp | 80 twp | 81 twp | 82 twp | 83 twp | 84 twp | 85 twp | 86 twp | 87 twp | 88 twp | 89 twp | 90 twp | 91 twp | 92 twp | 93 twp | 94 twp | 95 twp | 96 twp | 97 twp | 98 twp | 99 twp | 100 twp |
| french; charriere | 0.052914 F | 0.105828 F | 0.158742 F | 0.211656 F | 0.26457 F | 0.317484 F | 0.370398 F | 0.423312 F | 0.476226 F | 0.52914 F | 0.582054 F | 0.634968 F | 0.687882 F | 0.740796 F | 0.79371 F | 0.846624 F | 0.899538 F | 0.952452 F | 1.005366 F | 1.05828 F | 1.111194 F | 1.164108 F | 1.217022 F | 1.269936 F | 1.32285 F | 1.375764 F | 1.428678 F | 1.481592 F | 1.534506 F | 1.58742 F | 1.640334 F | 1.693248 F | 1.746162 F | 1.799076 F | 1.85199 F | 1.904904 F | 1.957818 F | 2.010732 F | 2.063646 F | 2.11656 F | 2.169474 F | 2.222388 F | 2.275302 F | 2.328216 F | 2.38113 F | 2.434044 F | 2.486958 F | 2.539872 F | 2.592786 F | 2.6457 F | 2.698614 F | 2.751528 F | 2.804442 F | 2.857356 F | 2.91027 F | 2.963184 F | 3.016098 F | 3.069012 F | 3.121926 F | 3.17484 F | 3.227754 F | 3.280668 F | 3.333582 F | 3.386496 F | 3.43941 F | 3.492324 F | 3.545238 F | 3.598152 F | 3.651066 F | 3.70398 F | 3.756894 F | 3.809808 F | 3.862722 F | 3.915636 F | 3.96855 F | 4.021464 F | 4.074378 F | 4.127292 F | 4.180206 F | 4.23312 F | 4.286034 F | 4.338948 F | 4.391862 F | 4.444776 F | 4.49769 F | 4.550604 F | 4.603518 F | 4.656432 F | 4.709346 F | 4.76226 F | 4.815174 F | 4.868088 F | 4.921002 F | 4.973916 F | 5.02683 F | 5.079744 F | 5.132658 F | 5.185572 F | 5.238486 F | 5.2914 F |
A twip (abbreviating "twentieth of a point", "twentieth of an inch point", or "twentieth of an Imperial point"[citation needed]) is a typographical measurement, defined as 1/20 of a typographical point. One twip is 1/1440 inch or 17.639 µm.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| twip | twp | ≡ 1⁄1440 in | = 1.7638×10−5 m | Imperial/US |
| twips | french; charriere | twips | french; charriere |
|---|---|---|---|
| 1 | = 0.052914 | 4 | = 0.211656 |
| 1.5 | = 0.079371 | 4.5 | = 0.238113 |
| 2 | = 0.105828 | 5 | = 0.26457 |
| 2.5 | = 0.132285 | 5.5 | = 0.291027 |
| 3 | = 0.158742 | 6 | = 0.317484 |
The French scale or French gauge system is commonly used to measure the size of a catheter. It is most often abbreviated as Fr, but can often be seen abbreviated as Fg, Ga, FR or F. It may also be abbreviated as CH or Ch (for Charrière, its inventor).
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| french; charriere | F | ≡ 1⁄3 mm | = 0.3×10−3 m | Other (Length) |
| french; charriere | twips | french; charriere | twips |
|---|---|---|---|
| 1 | = 18.898590165174 | 4 | = 75.594360660695 |
| 1.5 | = 28.347885247761 | 4.5 | = 85.043655743282 |
| 2 | = 37.797180330347 | 5 | = 94.492950825868 |
| 2.5 | = 47.246475412934 | 5.5 | = 103.94224590846 |
| 3 | = 56.695770495521 | 6 | = 113.39154099104 |
| twips | french; charriere |
|---|---|
| 1 | = 0.052914 |
| 18.8985902 | = 1 |
| Symbol | Definition |
|---|---|
| ≡ | exactly equal |
| ≈ | approximately equal to |
| = | equal to |
| digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |