Coil Calculator

If you make you own coils you know the typical questions: How many windings do I need? How long does my wire has to be? What is the resistance of my coil?

Warning: This calculator is for orientation only. Before using a new coil, it must be measured and checked for correct functionality.

WIRE

The coil calculator is a calculator for coils. You can use it to make coils based on any equation. It is especially useful for describing coils that are driven by alternating current.

The way a coil calculator works is this: You type in the values you want, and the calculator calculates how much wire you need. For example, if you want to coil a piece of wire 25 centimeters around a spool, you type 25 into the input box, and 25 centimeters into the output box.
The calculator uses mathematical equations and physics to figure out how much wire you need, and then gives you a list of parts to buy. You can type in your wire diameter, for example, and calculate the wire length you will need.
You can also type in the number of turns (turns per inch), and this will also calculate the length. However, if you want to change the coil diameter, you need to move all the numbers around the input box and change the diameter of each.
The coil calculator can be used in two ways. You can input the dimensions, and calculate all the dimensions in inches. Or you can input the dimensions in centimeters, for example, and calculate all the dimensions in centimeters.
To calculate the wire length in inches, type 25 into the input box, and then type .875 into both the input and output boxes. The calculator will calculate the wire length and the wire diameter.
To calculate the wire length in centimeters, for example, type 25 into the input box, and then type 1.4 into the output box. It will calculate the wire length and the wire diameter.
The calculator works best with rectangular coils. If you want to calculate a coil with rounded corners, you need to round the corners.
This calculator works only in metric units.

Supported Wires

Gold, Invar 36 / Nilo 36 / Pernifer 36, Kanthal A / AE / AF, Kanthal D, NiFe (Reactor Wire), NiFe30 (Resistherm), NiFe30 (StealthVape), Nichrome N20, Nichrome N40, Nichrome N60 (C), Nichrome N70 (B), Nichrome N80 (A), Nickel DH, Nickel Ni200 (TFR curve), Nickel Ni200 (linear TCR), Nifethal 52 (Alloy52), Nifethal 70 (Alloy120), Niobium alloy, SS 304, SS 316, SS 316L / Elite, SS 317L / Haywire, SS 430, Silver, Titanium 1, Titanium 2 (R50400), Titanium ready (e-SG), Tungsten

Coil inductance calculator

The coil calculator that accompanied this article explains how to build your own coil for magnetic fields. Coils are the heart of classical electromagnets, important because they produce magnetic fields. The formula for the coil’s magnetic field is shown below:

$$B = \frac{1}{4 \pi r^2} \times \frac{2 \pi r e (r / 0.05)}{r^2}$$
Where r is the radius of the coil in inches.

$$ 2 \pi r e (r / 0.05) = 1.22 \times 10^6
$$
To calculate the magnetic field of a typical coil, you take the volume of the coil and multiply by 0.05, the average radius of the coil.

$$ 0.05^2 \times 0.23^2 \times 0.3 = 1.59 \times 10^7
$$
This is a small magnet, and you need to know how powerful it is. The maximum magnetic field is 1.59 tesla, which is more than a million times stronger than the earth’s magnetic field. The earth’s magnetic field is about 0.005 tesla. So your magnet is stronger.
Your magnet is powerful enough, but it won’t be very useful unless you know how to control it. You can make it turn on and off with a switch.