The HFSS alternative for near-field coils.
Ansys HFSS is the reference full-wave solver for antennas and RF. Wireless power coils live in the near field, where a closed-form quasi-static solver answers the coupling question in seconds.
Last reviewed: October 2026
What HFSS does well
HFSS (High Frequency Structure Simulator) solves Maxwell's equations in full in 3D with the finite element method and automatic adaptive meshing. It is the tool RF engineers trust for antennas, filters, connectors, IC packages and signal integrity, and it sits inside Ansys Electronics Desktop next to Maxwell and Q3D.
For coils it captures what a quasi-static model cannot: self-resonance from parasitic capacitance, radiation, conductor and dielectric loss, and the effect of nearby metal and ferrite. At 13.56 MHz NFC and above, those effects become real design constraints.
Where AirInduct Sim is faster for WPT coils
Most wireless power design time goes on one question: how strongly do these two coils couple as the gap and offset change? That is a near-field, quasi-static problem, and full-wave machinery adds setup and run time without changing the answer for air-core coils well below self-resonance.
- L, M and k on every run, read directly, with no ports, de-embedding or Z-matrix post-processing.
- Gap and lateral misalignment sweeps in seconds using closed-form Biot–Savart and the Neumann integral.
- Eight WPT presets, including square Helmholtz and descending-turn (DTC) spirals.
- 3D field plots and a genetic optimizer in any browser, plus iOS and Android apps.
- An AI Copilot that drives the app and runs the real solver, and an MCP server for your own agents.
It is free to start: the free plan covers the Helmholtz topology with 3 simulations a month, and AirInduct Pro unlocks every topology, the AI Copilot and unlimited runs (see pricing).
Ansys HFSS vs AirInduct Sim at a glance
Where a full-wave RF solver and a quasi-static coil solver differ for WPT work.
| Criterion | AirInduct Sim | Ansys HFSS |
|---|---|---|
| Solver method | Closed-form Biot–Savart field + Neumann mutual inductance, no mesh | Full-wave 3D finite element method with adaptive meshing (plus integral-equation and asymptotic solvers) |
| Frequency range it is built for | kHz to low-MHz near-field coils (Qi, SAE J2954, 6.78 MHz, 13.56 MHz NFC sizing) | RF and microwave: antennas, filters, connectors, packages, signal integrity |
| Install | None — runs in the browser, plus iOS and Android apps | Windows or Linux desktop inside Ansys Electronics Desktop |
| Licence / price model | Free plan + Pro subscription | Commercial, quote-based; a limited free Student edition |
| Time to first result | Seconds from a topology preset | Minutes to hours: geometry, ports, boundaries, adaptive mesh passes |
| WPT outputs (L, M, k) | Self-inductance, mutual inductance M and coupling k on every run | S, Y or Z parameters; L, M and k derived from the impedance matrix |
| Ferrite, metal, radiation | Not modelled — air-core coils only, quasi-static | Yes: dispersive materials, conductor loss, radiation and far fields |
| Sweeps and optimisation | Gap, offset and turn sweeps plus a genetic optimizer in the app | Optimetrics parametric sweeps and optimisation |
| AI assistance | AI Copilot that drives the app and runs the real solver; MCP server for agents | Vendor AI assistant in recent releases |
Competitor details are taken from public vendor pages and documentation, last reviewed October 2026. Product names are trademarks of their respective owners and are used only to identify them. AirInduct is not affiliated with, endorsed by or sponsored by any of these vendors.
When to stay with HFSS
Stay with HFSS when the coil is part of an RF system: an NFC antenna next to a phone's metal chassis, a 13.56 MHz link where self-resonance and radiation matter, or any design that needs S-parameters for a matching network. AirInduct Sim does not model ferrite, metal or radiation.
Which should I use?
Use AirInduct Sim to size air-core wireless power coils and map coupling against gap and offset, and use HFSS when the coil becomes an RF component that needs materials, radiation and S-parameters. HFSS is the more complete solver; AirInduct Sim is the faster one for the near-field coupling question, and it runs in a browser. Many teams use both: AirInduct Sim to pick the topology and turns, HFSS to verify the final design.
Compare with other tools
See all 20 AirInduct Sim alternatives and comparisons →Get L, M and k before you draw a single port.
Frequently asked questions
Is HFSS a good tool for wireless power coils?
HFSS can model them, especially at 6.78 MHz and 13.56 MHz where parasitic capacitance and radiation start to matter. For kHz air-core coils it is far more solver than the problem needs: a quasi-static Biot–Savart solver gives L, M and k in seconds.
Is there a free alternative to Ansys HFSS?
For full-wave RF work, openEMS and MEEP are free open-source options. For near-field wireless power coils, AirInduct Sim has a free plan in the browser that returns inductance, mutual inductance and coupling without a mesh.
Can AirInduct Sim replace HFSS?
Not for antennas, radiation, S-parameters or anything with ferrite and metal. It replaces HFSS for the early question of how two air-core coils couple across gap and offset, and leaves HFSS for the final RF check.