Straight Wire Inductor Calculator
This calculator estimates the inductance of a straight round wire based on its length and diameter. It is useful in RF design, antenna modeling, and low-frequency inductive analysis where conductor shape affects circuit behavior.
Inductance Estimator for Straight Round Conductors
Straight Wire Inductance Formula
Where:
- $$L$$ = inductance (ฮผH)
- $$a$$ = length of the wire (cm)
- $$d$$ = diameter of the wire (cm)
This empirical formula provides an approximation for low-frequency applications with round conductors in air.
Straight Wire Inductance โ Calculation Example
Given:
- $$a$$ = 10 cm
- $$d$$ = 0.2 cm
Calculation:
- $$L = 0.00508 \cdot 10 \cdot \left( \log_{10} \left( \frac{2 \cdot 10}{0.2} \right) – 0.75 \right)$$
- $$= 0.0508 \cdot \left( \log_{10}(100) – 0.75 \right)$$
- $$= 0.0508 \cdot (2 – 0.75) = 0.0508 \cdot 1.25 โ 0.0635~\mu H$$
The inductance of a straight wire becomes important in high-speed, RF, and precision analog applications where even short conductor segments contribute reactance. This calculator helps engineers and hobbyists estimate inductance based on simple dimensions, particularly in antenna elements, jumper wires, and bus bars. For more accurate results at high frequencies, mutual coupling and skin effect should also be considered.