Capillary Rise Calculator
Calculate signed liquid rise or depression in a circular capillary from surface tension, contact angle, density and tube diameter.
YOUR CALCULATION
Result
—
Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Convert all values to SI and balance the vertical surface-tension force around the tube perimeter against the liquid-column weight. Preserve the sign of cos θ so non-wetting liquids report depression.
h=4γ cosθ/(ρgd)
Worked example
For γ=72 mN/m, θ=0°, density 1000 kg/m³ and diameter 0.25 mm, the ideal rise is about 0.11747 m. At θ=90° this model gives zero height; above 90° it gives a negative depression.
Assumptions and input details
Circular uniform tube, static liquid, constant density and surface tension, entered equilibrium contact angle and negligible tube-end/meniscus-volume effects. Contact angle is 0–180°. The result is an ideal equilibrium height, not a dynamic wicking rate or porous-media model.
References: OpenStax: surface tension and capillary action
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
Choose from 23 length definitions, including explicitly labelled regional measures. Area conversions square the length factor; geometric volumes cube it.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
Find the pressure increase with fluid depth, absolute pressure and the incremental force on a horizontal patch. Keep surface pressure separate from gauge pressure.
Infer dynamic viscosity from a circular tube’s measured flow, pressure drop and fully developed laminar geometry.
Find density, mass or volume from the other two values. Choose international and regional units and inspect the formula and unit-conversion tables.
Reserved advertising space.