Coil math you can trust, before you cut a single wire.

ResCalc calculates the resistance of electric heating coils — from simple round wire to complex multi-strand alien builds.

Describe count, shape, size and metal, set diameter and turns, and get resistance, wattage recommendation and heat development. Built by a coil builder, not a spreadsheet.

Describe the wire. Get the truth.

Count, shape, size, metal — stack as many core wires as your build needs. Set inner diameter, turns, legs and fuse, and ResCalc recommends the wattage to match.

Every build you ever dialed in, saved.

The Coil Locker keeps your builds with full specs — wires, diameter, turns, resistance. Rebuild a proven coil months later without guessing what made it good.

Show your work. Steal like a builder.

Add photos to your builds and share them with the community — full spec card included. Browse other builders' coils, like, comment, and download a build straight into your locker.

One coffee. Yours forever.

Measure twice. Wrap once.

Know your resistance before the first wrap. Built by a coil builder in Vienna.