Conversion method
Force per unit length along an interface. Temperature and composition affect the measured value.
mN/m = x × 1000
10 N/m = 10000 mN/m.
| N/m | mN/m |
|---|---|
| 1 | 1000 |
| 5 | 5000 |
| 10 | 10000 |
| 25 | 25000 |
| 50 | 50000 |
| 100 | 100000 |
Unit definitions and sources
Force per unit length along an interface. Temperature and composition affect the measured value.
| Unit and system | Use | Definition | Relationship |
|---|---|---|---|
| Newton per meter (N/m); si | Common units | Newton per meter: base (n-m) = value × 1. Common use: Surface Tension. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Millinewton per meter (mN/m); si | Common units | Millinewton per meter: base (n-m) = value × 0.001. Common use: Surface Tension. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Dyne per centimeter (dyn/cm); si | Specialist units | Dyne per centimeter: base (n-m) = value × 0.001. Common use: Surface Tension. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Pound-force per foot (lbf/ft); si | Specialist units | Pound-force per foot: base (n-m) = value × 14.593902937206362. Common use: Surface Tension. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Gram-force/centimeter (gf/(cm)); other | Specialist units | gram-force/centimeter = 0.980665 n-m, derived from the component SI/customary definitions. Common use: Surface Tension. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Pound-force/inch (lbf/(in)); other | Specialist units | pound-force/inch = 175.12683524647636 n-m, derived from the component SI/customary definitions. Common use: Surface Tension. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
Sources: NIST: SP 811 Appendix B.8: conversion factors; BIPM: SI prefixes
Precision of surface tension conversions
All 6 surface tension units convert through Newton per meter (N/m). 6 have an exact defined relationship to the base unit and 0 are conventional or measured values. Results and the tables on this page come from the same engine, so a table value can be checked against the converter directly.
Standard display shows up to six decimal places, switching to scientific notation for very large or small values. Calculation uses JavaScript binary floating point independently of display rounding, so extra digits are not a claim about measurement accuracy. Each unit lists its own source; a citation records where the definition comes from, not an independent review. See Conversion methodology for the review and correction process.