Mass Moment of Inertia Converter
Convert rotational mass inertia between kg·m², g·cm² and mass-pound square-length units.
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
Convert mass and square the length factor, preserving the stated axis and mass distribution.
I_SI=value×kg per mass unit×(meters per length unit)²
Worked example
1 mass lb·ft² is approximately 0.0421401101 kg·m². One g·cm² is 10⁻⁷ kg·m².
Assumptions and input details
This is mass moment of inertia about an already specified axis. lb denotes avoirdupois mass pounds, not lbf or slugs. Changing units does not change the reference axis; parallel-axis adjustments require geometry and mass. Area second moments in m⁴ are a separate quantity.
References: NIST: unit conversion factors
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.
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