Magnetic component design,
at the speed of an HTTP request.

From customer spec to a manufacturable transformer or inductor — turns, air gap, wire, losses, hotspot — without installing anything.

Open Calculator Browse Core LibraryNo install · Runs locally · Free to use
Quick EstimateFirst run loads on demand · subsequent runs instant
6
Topology presets
LLC · Flyback · Forward · Planar · PFC · CM
797
Cores indexed
Major ferrite & powder vendors
194
Materials
Ferrite · MPP · Sendust · Nanocrystalline
194
Wires & litz
+ 88 bobbin part numbers

An engineer's tool, not a one-page calculator.

Faraday turns, Steinmetz core loss with temperature dependence, Dowell AC resistance with porosity correction, Roshen iterative fringing, McLyman area-product core selection, lumped thermal RC — the same equations a textbook designer uses, automated.

Faithful physics

Steinmetz core loss with temperature dependence, Dowell AC resistance with porosity correction, Roshen iterative fringing, McLyman Ap selection, lumped thermal RC. The same equations a textbook designer uses, automated.

Vendor data, curated

Cores, materials, wires and bobbins from leading vendors — calibrated Pcv coefficients, Bsat(T), DC bias curves, AEC-Q200 grading, IEC creepage. Updated periodically.

Standards-aware

IEC 62368 creepage / clearance, UL 1446 insulation systems, AEC-Q200 grading, IEC 60664-1 Paschen derate. Designs flagged before they leave the calculator.

Your IP stays in your browser

No telemetry, no spec uploads, no cloud round-trip. The engine downloads to your tab once and runs on the same RAM your spec lives in. Disconnect after first load — still works.

Engineering-grade exports

ISO 7200 spec sheet (Markdown / PDF), IEC 63278 AAS submodel, JEDEC JEP30 PartModel, FEMM Lua script for verification, Tier-A SPICE subcircuit.

Designs never leave your machine.

The Web Lite architecture serves the engine as a static asset. Your spec, your turns count, your loss numbers — they exist only in this tab. Use it on a flight, in a SCIF, behind an air gap.

Ready to design something?

Six topology families covered today — LLC, Flyback, Forward, Planar, PFC choke, CM choke.

Open Calculator