Moment of Inertia Converter
Convert between 8 moment of inertia units instantly. Enter a value, pick your units and get the result with the formula, a full conversion table and worked examples.
1 lb·ft² in all moment of inertia units
Updates live as you type. Click a row to set it as the target unit.
| Unit | Symbol | Value |
|---|---|---|
| Gram sq centimetre | g·cm² | 421,401 |
| Kilogram sq millimetre | kg·mm² | 42,140.1 |
| Ounce sq inch | oz·in² | 2,304 |
| Kilogram sq centimetre | kg·cm² | 421.401 |
| Pound sq inch | lb·in² | 144 |
| Pound sq foot | lb·ft² | 1 |
| Kilogram sq metre | kg·m² | 0.0421401 |
| Slug sq foot | slug·ft² | 0.031081 |
How to Convert Moment of Inertia Units
Moment of inertia is a body's resistance to angular acceleration. The SI unit is kilogram square metre (kg·m²); motor and load inertia values are needed when sizing servo drives and VFD ramp times.
Every unit on this page is stored as a fixed factor relative to one reference unit, the kilogram sq metre (kg·m²). Converting is a two step multiply and divide:
- Multiply your value by the factor of the source unit to get the value in kg·m².
- Divide that result by the factor of the target unit.
Pound sq foot to Kilogram sq metre conversion table
| Pound sq foot (lb·ft²) | Kilogram sq metre (kg·m²) |
|---|---|
| 1 lb·ft² | 0.0421401 kg·m² |
| 2 lb·ft² | 0.0842802 kg·m² |
| 3 lb·ft² | 0.12642 kg·m² |
| 4 lb·ft² | 0.16856 kg·m² |
| 5 lb·ft² | 0.210701 kg·m² |
| 6 lb·ft² | 0.252841 kg·m² |
| 7 lb·ft² | 0.294981 kg·m² |
| 8 lb·ft² | 0.337121 kg·m² |
| 9 lb·ft² | 0.379261 kg·m² |
| 10 lb·ft² | 0.421401 kg·m² |
| 15 lb·ft² | 0.632102 kg·m² |
| 20 lb·ft² | 0.842802 kg·m² |
| 25 lb·ft² | 1.0535 kg·m² |
| 30 lb·ft² | 1.2642 kg·m² |
| 40 lb·ft² | 1.6856 kg·m² |
| 50 lb·ft² | 2.10701 kg·m² |
| 75 lb·ft² | 3.16051 kg·m² |
| 100 lb·ft² | 4.21401 kg·m² |
| 250 lb·ft² | 10.535 kg·m² |
| 500 lb·ft² | 21.0701 kg·m² |
| 1,000 lb·ft² | 42.1401 kg·m² |
Moment of Inertia Units and Conversion Factors
Value of one unit expressed in kg·m².
| Unit | Symbol | In kg·m² |
|---|---|---|
| Gram sq centimetre | g·cm² | 1 × 10−7 |
| Kilogram sq millimetre | kg·mm² | 0.000001 |
| Ounce sq inch | oz·in² | 0.00001828997834 |
| Kilogram sq centimetre | kg·cm² | 0.0001 |
| Pound sq inch | lb·in² | 0.0002926396534 |
| Pound sq foot | lb·ft² | 0.04214011009 |
| Kilogram sq metre | kg·m² | 1 |
| Slug sq foot | slug·ft² | 1.355817948 |
Frequently Asked Questions
What is the SI unit of moment of inertia?
The SI unit of moment of inertia is the kilogram sq metre (kg·m²). Moment of inertia is a body's resistance to angular acceleration.
How do I convert kg·m² to lb·ft²?
To convert kilogram sq metre (kg·m²) to pound sq foot (lb·ft²), multiply the value in kg·m² by 23.7304. For example, 1 kg·m² = 23.7304 lb·ft².
How do I convert lb·ft² to kg·m²?
To convert pound sq foot (lb·ft²) to kilogram sq metre (kg·m²), multiply the value in lb·ft² by 0.0421401. For example, 1 lb·ft² = 0.0421401 kg·m².
How do I convert kg·cm² to kg·m²?
To convert kilogram sq centimetre (kg·cm²) to kilogram sq metre (kg·m²), multiply the value in kg·cm² by 0.0001. For example, 1 kg·cm² = 0.0001 kg·m².
Can I see a value in every moment of inertia unit at once?
Yes. Enter a value and choose the source unit; the "all units" table below the converter instantly lists the equivalent in all 8 supported units. Click any row to make it the target unit.
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