Electromagnetic and Thermal Unit Converter
A converter with only the quantities a power-magnetics or thermal engineer actually reaches for - no cooking measures, no astronomical units. It keeps the distinction between an absolute temperature and a temperature difference, which most general converters get wrong.
Why this converter is deliberately small
General-purpose converters carry thousands of units, and the cost is that the two entries you need sit twenty rows apart from things you will never use. Everything here is a quantity that turns up in magnetics, power electronics or thermal design.
One distinction worth calling out: temperature and temperature difference are separate quantities. 180 degF as an absolute temperature is 82.2 degC; 180 degF as a rise is 100 K. Converters that offer only the first silently give the wrong answer for a thermal resistance calculation.
Supported quantities and units
Geometry
| Length | m, mm, cm, um, nm, km, mil, in, ft |
| Area | m^2, mm^2, cm^2, in^2, cmil, kcmil |
| Volume | m^3, mm^3, cm^3, L, in^3 |
Electromagnetic
| Frequency | Hz, kHz, MHz, GHz, rad/s, rpm |
| Inductance | H, mH, uH, nH, pH |
| Capacitance | F, mF, uF, nF, pF |
| Resistance | Ohm, mOhm, uOhm, kOhm, MOhm |
| Resistivity | Ohm*m, uOhm*m, nOhm*m, Ohm*cm, uOhm*cm, Ohm*mm^2/m |
| Electrical conductivity | S/m, MS/m, S/mm, %IACS |
| Magnetic flux density (B) | T, mT, uT, G, kG, Wb/m^2 |
| Magnetic field strength (H) | A/m, kA/m, A/mm, Oe, At/m |
| Magnetic flux | Wb, mWb, uWb, Mx, V*s |
| Permeability | H/m, uH/m, nH/m, mu0 |
| Magnetomotive force | A*t, A, kA*t, Gb |
| Current | A, mA, uA, kA |
| Current density | A/m^2, A/mm^2, A/cm^2, A/in^2, A/kcmil |
| Voltage | V, mV, uV, kV |
Thermal
| Power | W, mW, kW, MW, BTU/h, hp |
| Volumetric power density | W/m^3, kW/m^3, W/cm^3, mW/cm^3, W/L |
| Specific (mass) loss | W/kg, mW/g, W/g, mW/kg |
| Heat flux | W/m^2, kW/m^2, W/cm^2, BTU/(h*ft^2) |
| Energy | J, mJ, kJ, Wh, kWh, cal, BTU, eV |
| Temperature (absolute) | K, degC, degF |
| Temperature difference | K, degC, degF |
| Thermal conductivity | W/(m*K), mW/(m*K), W/(cm*K), BTU/(h*ft*degF) |
| Heat transfer coefficient | W/(m^2*K), W/(cm^2*K), BTU/(h*ft^2*degF) |
| Thermal resistance | K/W, degC/W, degC/mW, degF*h/BTU |
| Specific heat capacity | J/(kg*K), kJ/(kg*K), J/(g*K), cal/(g*degC), BTU/(lb*degF) |
| Velocity | m/s, km/h, ft/s, ft/min, mph |
General
| Density | kg/m^3, g/cm^3, kg/dm^3, lb/in^3 |
| Mass | kg, g, mg, t, lb, oz |
| Time | s, ms, us, ns, min, h |
| Angle | rad, deg, mrad |