| name | unit-converter |
| description | Mechanical engineering unit conversion — stress, force, pressure, length, area, moment of inertia, torque, power, temperature, thermal properties, flow rate, viscosity. Imperial ↔ SI ↔ metric. |
| metadata | {"priority":6,"promptSignals":{"phrases":["convert","unit conversion","imperial to SI","ksi to MPa","psi to","inches to","hp to kW"],"minScore":3}} |
Unit Converter — Mechanical Engineering
Always show: original value → converted value with full precision. Show formula used.
Stress / Pressure
1 psi = 6.895 kPa = 0.006895 MPa
1 ksi = 6.895 MPa
1 MPa = 145.0 psi = 0.1450 ksi
1 bar = 0.1 MPa = 14.50 psi
1 atm = 101.325 kPa = 14.696 psi
1 kgf/cm² = 98.07 kPa = 14.22 psi
Force
1 lbf = 4.448 N
1 N = 0.2248 lbf
1 kip = 1000 lbf = 4448 N = 4.448 kN
1 kgf = 9.807 N
Length
1 in = 25.40 mm
1 ft = 0.3048 m = 304.8 mm
1 mm = 0.03937 in
1 m = 39.37 in = 3.281 ft
1 mil = 0.001 in = 0.0254 mm
Area
1 in² = 645.2 mm² = 6.452 cm²
1 ft² = 0.0929 m²
1 mm² = 0.001550 in²
Moment of Inertia (Second Moment of Area)
1 in⁴ = 416,231 mm⁴ = 41.623 cm⁴
1 mm⁴ = 2.403×10⁻⁶ in⁴
1 cm⁴ = 0.02403 in⁴
Section Modulus
1 in³ = 16,387 mm³
1 mm³ = 6.102×10⁻⁵ in³
Moment / Torque / Bending Moment
1 lbf·in = 0.1130 N·m = 113.0 N·mm
1 lbf·ft = 1.356 N·m
1 kip·in = 112.98 N·m = 0.11298 kN·m
1 N·m = 8.851 lbf·in = 0.7376 lbf·ft
1 kN·m = 8851 lbf·in = 737.6 lbf·ft
Power
1 hp = 746 W = 0.746 kW = 550 ft·lbf/s = 33,000 ft·lbf/min
1 kW = 1.341 hp
1 W = 1 N·m/s = 1 J/s
Speed / Angular Velocity
1 rpm = 2π/60 rad/s = 0.10472 rad/s
1 rad/s = 9.549 rpm
1 Hz = 1 cycle/s = 2π rad/s (angular freq ω = 2πf)
Velocity
1 ft/s = 0.3048 m/s = 0.6818 mph
1 m/s = 3.281 ft/s = 3.600 km/h
1 mph = 1.467 ft/s = 0.4470 m/s
1 km/h = 0.2778 m/s
Temperature
°C = (°F - 32) × 5/9
°F = °C × 9/5 + 32
K = °C + 273.15
°R = °F + 459.67
Mass / Weight
1 lbm = 0.4536 kg (mass)
1 lbf = 4.448 N (force; 1 lbm weighs 1 lbf at g=32.174 ft/s²)
1 slug = 14.59 kg (F=ma with lbf and ft/s²)
1 kg = 2.205 lbm
1 tonne (metric) = 1000 kg = 2205 lbm
Thermal Conductivity
1 BTU/(hr·ft·°F) = 1.731 W/(m·K)
1 W/(m·K) = 0.5779 BTU/(hr·ft·°F)
Heat Transfer Coefficient h
1 BTU/(hr·ft²·°F) = 5.678 W/(m²·K)
1 W/(m²·K) = 0.1761 BTU/(hr·ft²·°F)
Heat Flux
1 BTU/(hr·ft²) = 3.155 W/m²
1 W/m² = 0.3170 BTU/(hr·ft²)
Specific Heat
1 BTU/(lbm·°F) = 4187 J/(kg·K) = 4.187 kJ/(kg·K)
1 J/(kg·K) = 2.389×10⁻⁴ BTU/(lbm·°F)
Thermal Resistance
1 °F·hr/BTU = 1.895 K/W
1 K/W = 0.5275 °F·hr/BTU
Viscosity (Dynamic μ)
1 cP (centipoise) = 0.001 Pa·s = 0.001 N·s/m²
1 Pa·s = 1000 cP = 0.6720 lbm/(ft·s)
1 lbm/(ft·s) = 1.488 Pa·s
Water at 20°C: μ = 1.002 cP = 0.001002 Pa·s
Air at 20°C: μ = 0.0182 cP = 1.82×10⁻⁵ Pa·s
Kinematic Viscosity ν = μ/ρ
1 cSt = 1 mm²/s = 10⁻⁶ m²/s
1 ft²/s = 0.0929 m²/s
Water at 20°C: ν = 1.004 cSt = 1.004×10⁻⁶ m²/s
Air at 20°C: ν = 15.11 cSt = 15.11×10⁻⁶ m²/s
Flow Rate
1 gpm (US gallon/min) = 6.309×10⁻⁵ m³/s = 0.06309 L/s = 3.785 L/min
1 L/s = 15.85 gpm
1 m³/s = 15,850 gpm = 1000 L/s
1 cfm (ft³/min) = 0.02832 m³/min = 0.4719 L/s
Density
1 lbm/ft³ = 16.018 kg/m³
1 kg/m³ = 0.06243 lbm/ft³
Water: 1000 kg/m³ = 62.43 lbm/ft³
Steel: 7850 kg/m³ = 490 lbm/ft³
Aluminum: 2700 kg/m³ = 169 lbm/ft³