Guitar pickup winding calculator
How many turns, how much wire, and a 3D printable bobbin built from your own dimensions
Input data
The three dimensions below describe the core, meaning whatever the wire is wound onto, not the finished coil and not the pickup. On a Fender single coil there is no former under the wire: the core is the row of magnets itself.
Results
- Turns per layer:
- Turn count:
- Wire length:
- Calculated resistance:
- Coil thickness:
- Inductance:
North coil
- Turns per layer:
- Turn count:
- Wire length:
- Calculated resistance:
- Coil thickness:
- Inductance:
South coil
- Turns per layer:
- Turn count:
- Wire length:
- Calculated resistance:
- Coil thickness:
- Inductance:
Complete pickup
- Inductance, both coils in series:
Air-core estimate. Steel slugs, screws and keeper bars raise the real value, typically by about a factor of two on a humbucker. Mutual coupling between the two coils is not included.
Output level
Resonant peak in the circuit
- Resonant frequency:
- Peak height:
Assembly
The diagram is a top view, pole pieces facing you. For a humbucker to be in phase and quiet, its two coils must differ in two ways at once: the winding direction and the magnet orientation. One difference alone is not enough. Two identical windings let the hum through, two identical magnets give a thin sound. The mirror of this drawing works just as well, with CCW and north up on the left. If your winder only turns one way, wind both coils alike, flip one magnet, and join the two starts together: the reversal then comes from the wiring instead of the winding. Lead colours change from one maker to the next, follow the diagram that came with yours.
Drag to rotate · 0 triangles
Former with rounded ends, sized from your dimensions, flanges clearing the calculated winding. The rounded ends are true cylinders and the pole holes true circles, at their exact diameter. Open it in a CAD program to check it before printing.
The machine file button opens the coil winder with these dimensions and the resistance of the coil. That page works out its own turn count, the layers, the points where the wire turns back, and the file the machine runs. It asks for a few turns more than the count above, about three quarters of a percent: a machine lays the turns against each other, a scatter wind does not, so its turns are shorter.
Reference pickups
Load a known pickup to compare the model against published and measured figures.
Enter the dimensions of your core, the wire gauge and the resistance you are aiming for. The tool tells you how many turns that takes and how much wire you will go through, then estimates the inductance.
From the same dimensions it also builds a bobbin former and exports it as a STEP file, so you can 3D print it and wind on it. It is generated from what you typed rather than picked off a shelf, so the pole holes, the pole spacing and the winding window are yours. Turn it around in the 3D preview before you download it.
Frequently asked questions
What does the pickup winding calculator do?
From your core dimensions, wire gauge and target resistance, it works out how many turns you need and how much wire that is, then estimates the inductance. It also generates a matching bobbin former you can 3D print.
Which dimensions should I enter?
Those of the core, meaning whatever the wire is wound onto, not the finished coil and not the pickup. On a Fender single coil there is no former under the wire, so the core is the row of magnets: about 57 mm long by 5 mm thick. Entering the size of the pickup instead gives a wrong answer with no warning.
Can I 3D print the bobbin?
Yes. The bobbin former is built from the dimensions you entered, not picked from a library of fixed models, and downloads as a STEP file. You choose the number of pole holes, or zero for a blade, the pole spacing your guitar needs, and the hole clearance so the pole pieces actually go in. A humbucker gives two bobbins side by side in one file.
Why a STEP file and not an STL?
Because STEP carries real cylinders, so a 5.2 mm pole hole really measures 5.2 mm, where a twelve sided polygon only measures 5.02 mm across the flats, and that is enough to stop a 5 mm pole going in. PrusaSlicer, OrcaSlicer and Bambu Studio open STEP directly; with an older slicer, open it in any CAD package and export an STL from there. That way the mesh is made at the resolution you want rather than baked into the download.
Can I use it for humbuckers?
Yes. Tick the humbucker option to model two coils, each with its own wire gauge. The resistance you enter is that of the complete pickup, both coils in series.
How accurate is it?
The wire length is the most reliable figure, since it follows directly from the resistance and the gauge. The turn count lands within a few percent if your dimensions are right. The inductance goes through a magnetic model fitted on 38 measured pickups and sits around 20 to 25 percent out, so read it as an order of magnitude. One thing to keep in mind: the wire table is given at 20 degrees, and copper gains 0.4 percent per degree, so a warm workshop shifts the turn count by one or two percent.
Which end of each coil goes where?
Ground to the start of coil 1, finish of coil 1 to the start of coil 2, finish of coil 2 to hot. The two coils are then in series and travelled in the same order, which is why the reversal has to come from the winding direction. If you wound both coils the same way, join the two starts instead and flip one magnet: one reversal on the electrical side, one on the magnetic side, never two on the same side.
Is the south magnet always toward the bridge, and the hot on that side?
No, neither is fixed. Inside one humbucker only the difference between the two coils counts: one north up and one south up, one clockwise and one counter-clockwise. Both mirror images give the same pickup, which is why two of the eight combinations work. The choice only becomes constrained when the pickup lives with others: the coil carrying the hot is the one a coil split usually keeps, and a neck and bridge pair has to be built alike to stay in phase in the middle position.
Compare against the pickup specifications chart: resistance and measured inductance for common models.
Try our guitar fret calculator as well, or the pickup coil winder if you wind your own.