Hi, there is no layer thickness setting in the EDA as far as I know, but you'd need to see what you PCB manufacturer can offer and use that for your calculations. If you are going to use JLCPCB, here are their capabilities: [https://jlcpcb.com/capabilities/Capabilities](https://jlcpcb.com/capabilities/Capabilities)<br> <br> 4/6 layer impedance info: [https://cart.jlcpcb.com/impedance](https://cart.jlcpcb.com/impedance) And a calculation tool: [https://cart.jlcpcb.com/impedanceCalculation](https://cart.jlcpcb.com/impedanceCalculation)<br> <br> If you are going to use other manufacturers, you need to find that out from them. Another great and free tool for a lot of PCB design is Saturn PCB Design Toolkit: [https://saturnpcb.com/saturn-pcb-toolkit/](https://saturnpcb.com/saturn-pcb-toolkit/) It's free but you need to give them your email to download it.

I can recommend this: [http://mdtlc.sourceforge.net/](http://mdtlc.sourceforge.net/)<br> <br> It is a Free and Open Source Software 2D field solver that gives results comparable to commercial field solvers.