Convert Gram-force per Centimeter to Poundals per Inch
Gram-force per Centimeter (gf/cm) to Poundal per Inch (pdl/in) surface tension conversion — enter any value below to get an instant result, or use the table for common values.
Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.
Result
1 gf/cm = 0.18016635 pdl/in
1 Gram-force per Centimeter = 0.18016635 Poundals per Inch
1 Poundal per Inch = 5.550426 Gram-force per Centimeter
1 gf/cm in every supported unit
Conversion chart: Gram-force per Centimeter to Poundals per Inch
Conversion table
| Gram-force per Centimeter (gf/cm) | Poundal per Inch (pdl/in) |
|---|---|
| 0.01 gf/cm | 0.0018016635 pdl/in |
| 0.1 gf/cm | 0.018016635 pdl/in |
| 1 gf/cm | 0.18016635 pdl/in |
| 2 gf/cm | 0.3603327 pdl/in |
| 3 gf/cm | 0.54049906 pdl/in |
| 5 gf/cm | 0.90083176 pdl/in |
| 10 gf/cm | 1.8016635 pdl/in |
| 20 gf/cm | 3.603327 pdl/in |
| 50 gf/cm | 9.0083176 pdl/in |
| 100 gf/cm | 18.016635 pdl/in |
| 1000 gf/cm | 180.16635 pdl/in |
Gram-force per Centimeter (gf/cm)
Definition: A gravitational-metric unit expressing surface tension as the weight of a gram mass (under standard gravity) acting per centimeter of surface length, rather than a true dyne-based force unit.
History: Reflects an older engineering convention of measuring force in terms of the weight it takes to balance, common before force units were cleanly separated from mass units in everyday lab practice.
Current use: Occasionally appears in older chemistry texts and instrument manuals, particularly those built around simple weight-balance style tensiometers.
Poundal per Inch (pdl/in)
Definition: A US customary/imperial surface-tension unit built from the poundal — the absolute (mass-based, gravity-independent) force unit in the foot-pound-second system — per inch of surface length.
History: Part of the older "absolute" foot-pound-second (FPS) system of units, which defined force directly from mass and acceleration (the poundal) rather than from a gravitational weight standard, paralleling how the newton relates to the kilogram.
Current use: Rarely used today outside of historical British and American engineering texts that favored the poundal-based absolute FPS system over the more common pound-force-based gravitational system.
Supported Units
| Unit | Symbol | In N/m |
|---|---|---|
| Newton per Meter | N/m | 1 N/m |
| Millinewton per Meter | mN/m | 0.001 N/m |
| Dyne per Centimeter | dyn/cm | 0.001 N/m |
| Gram-force per Centimeter | gf/cm | 0.980665 N/m |
| Erg per Square Centimeter | erg/cm² | 0.001 N/m |
| Erg per Square Millimeter | erg/mm² | 0.1 N/m |
| Poundal per Inch | pdl/in | 5.4431085 N/m |
| Pound-force per Inch | lbf/in | 175.12684 N/m |
About These Parameters
- Value
- The surface tension value you want to convert, expressed in the "From" unit. Accepts decimals.
- From Unit
- The unit your input value is currently measured in — a chemistry lab's dyn/cm, or an SI-based data sheet's N/m.
- To Unit
- The unit you want the result converted into. Use the swap button to flip From and To instantly.
How Surface Tension Conversion Works
The Formula
Every unit here is defined by a fixed multiplier relative to newtons per meter. To convert a value from one unit to another:
result = value × (factor of "From" unit ÷ factor of "To" unit)
For Gram-force per Centimeter → Poundal per Inch: multiply by 0.18016635. For example, 1 gf/cm × 0.18016635 = 0.18016635 pdl/in.
Force per Length vs. Energy per Area
Surface tension can be measured either as a force divided by a length (like N/m or dyn/cm) or as an energy divided by an area (like erg/cm²) — and the two are dimensionally identical, not just numerically similar. Work equals force × distance, and area equals length × length, so force ÷ length works out to (force × length) ÷ length² = energy ÷ area. That's why 1 dyn/cm and 1 erg/cm² are the exact same physical quantity: stretching a liquid's surface by one unit of length against one unit of tension takes exactly one unit of surface energy.
Everyday Reference Values
Pure water sits at roughly 72.8 dyn/cm (72.8 mN/m) at 20°C, one of the highest surface tensions among common liquids because water molecules hydrogen-bond strongly to each other. Adding soap or other surfactants can cut that by more than half, down to around 25-30 dyn/cm, which is exactly why soap solutions form thin, stretchy bubble films that plain water can't. At the other extreme, liquid mercury's strong metallic bonding gives it a surface tension near 487 dyn/cm — over six times water's — which is why mercury beads up sharply into tight droplets rather than spreading or wetting a surface.
Example
A surface tension of 1 gf/cm equals 0.18016635 pdl/in. For scale, that's roughly 980.665 dyn/cm — compare that to pure water's approximately 72.8 dyn/cm at room temperature to judge whether this value is closer to a plain liquid or a surfactant solution.
Frequently Asked Questions
How many Poundals per Inch are in 1 Gram-force per Centimeter?
1 Gram-force per Centimeter (gf/cm) equals exactly 0.18016635 Poundals per Inch (pdl/in).
What is surface tension?
Surface tension is the force per unit length that acts along the surface of a liquid, arising from the cohesive attraction between the liquid's molecules pulling each other inward. It's what causes liquids to minimize their surface area, forming droplets and supporting small floating objects like insects or a carefully placed needle.
Why is surface tension measured in both N/m and erg/cm²?
The two are dimensionally equivalent because energy equals force × distance and area equals length². Whether you frame surface tension as a mechanical force pulling along a line (N/m, dyn/cm) or as the surface free energy needed to create new surface area (erg/cm²), the physical quantity and its numeric value in matched CGS units are identical.
How accurate are these conversions?
Every conversion factor used here is the exact, internationally recognized relationship between the underlying force, energy, and length units — results are limited only by floating-point display precision, not by rounded conversion constants.
Why does soapy water have lower surface tension than plain water?
Soap molecules are surfactants — one end is attracted to water, the other repelled by it — so they migrate to the water's surface and disrupt the hydrogen bonding between water molecules that produces high surface tension. That's why soap solutions can form thin, stable bubble films (surface tension around 25-30 dyn/cm) that plain water (about 72.8 dyn/cm) cannot sustain.