Air Column Resonance Calculator
List ideal resonance frequencies and wavelengths for an open–open pipe or a pipe closed at one end.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Add the explicitly entered end correction to obtain effective length. An open–open column supports every positive integer harmonic; a one-end-closed column supports only odd harmonics.
Open–open: f_n=n c/(2L_eff); closed–open: f_n=n c/(4L_eff), n=1,3,5,…
Worked example
With effective length 0.5 m and sound speed 343 m/s, an open–open column has fundamental 343 Hz. A one-end-closed column of the same length has fundamental 171.5 Hz and next resonance 514.5 Hz.
Assumptions and input details
Ideal one-dimensional uniform air column with rigid boundaries, constant entered sound speed and small disturbances. End correction is entered rather than inferred; use zero to omit it. Diameter, flaring, temperature gradients, losses, radiation, wall compliance, excitation strength and resonance amplitude are excluded. The closed-column list labels odd harmonic numbers rather than renumbering them as consecutive harmonics.
References: Howard University Physics: resonance of air columns
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.
SI prefixes are explicit: for example, milli means one thousandth, micro one millionth and kilo one thousand. Changing a unit changes the interpretation of the entered number.
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.
Calculate wave speed, frequency or wavelength from the other two. Convert units, find the period and view an illustrative normalized wave.
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