Calculate inductance from inductive reactance and frequency, or solve for reactance or frequency. Optional series-RL impedance, phase and power factor use an entered resistance estimate; coil DC resistance may underestimate frequency-dependent AC losses.

Ideal linear inductor in sinusoidal steady state: XL = 2ฯ€fL. Ohms must represent inductive reactance, not coil resistance or total impedance magnitude.

Optional settings

Blank omits impedance and phase. Coil DC resistance is only an approximation for AC series resistance.

Ohms To Henries Formula

The following formula calculates inductance from inductive reactance at a given frequency for an ideal linear inductor in sinusoidal steady state. Total impedance magnitude and DC coil resistance are not interchangeable with inductive reactance.

L = XL / (2 ร— ฯ€ ร— f)

Variables:

  • L is the inductance in henries (H)
  • XL is the inductive reactance in ohms (ฮฉ)
  • f is the frequency in hertz (Hz)
  • ฯ€ is the mathematical constant pi (~3.14159)
Inductance to Reactance Conversion Table (XL = 2ฯ€ f L, f = 1.000 kHz)
Inductance (H) Reactance (ฮฉ)
0.0000010.006
0.00000220.014
0.00000470.030
0.0000100.063
0.0000220.138
0.0000330.207
0.0000470.295
0.0000680.427
0.0001000.628
0.0002201.382
0.0003302.073
0.0004702.953
0.0006804.273
0.0010006.283
0.00220013.823
0.00470029.531
0.01000062.832
0.022000138.230
0.047000295.310
0.100000628.319
* Reactance rounded to 3 decimals. Uses XL = 2ฯ€ f L with f = 1 kHz (inductive reactance increases linearly with frequency).

What Is an Ohms To Henries Calculation?

โ€œOhms to henriesโ€ typically refers to calculating inductance (in henries) from inductive reactance (measured in ohms) at a specific frequency. Since ohms and henries measure different electrical properties, you cannot convert plain resistance into inductance without additional context. For inductors, the key relationship is between inductive reactance, frequency, and inductance.

How to Calculate Ohms To Henries?

The following steps outline how to calculate the Ohms To Henries.

  1. First, determine the inductive reactance in ohms (XL).
  2. Next, determine the frequency in hertz (f).
  3. Next, use the formula from above: L = XL / (2 * ฯ€ * f).
  4. Finally, calculate the inductance in henries (H).
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

inductive reactance in ohms (XL) = 50

frequency in hertz (f) = 100

mathematical constant pi (ฯ€ โ‰ˆ 3.14159)

Solution: L = XL / (2ฯ€f) = 50 / (2ฯ€ ยท 100) = 0.0796 H (โ‰ˆ 79.6 mH).