Free alternatives to OrCAD

Cadence's schematic, PCB and PSpice simulation tools. Here are 3 free options, most popular first.

KiCad

PCB & electronics

Open-source electronics design automation suite

Stars: ★ 3k
Licence: GPL-3.0
Updated: yesterday

Alternative to Altium Designer, Eagle

Qucs-S

PCB & electronics

Circuit simulator GUI using ngspice, Xyce and other engines

Stars: ★ 1.4k
Licence: GPL-2.0
Updated: 2 days ago

Alternative to OrCAD

ngspice

PCB & electronics

Open-source mixed-signal SPICE circuit simulator

Licence: BSD-3-Clause
Updated: 3 days ago

Alternative to OrCAD

Check file compatibility before switching. Free tools import STEP, DXF and other neutral formats well, but native SolidWorks, Altium or Revit files, drawing standards and PDM workflows may not carry over cleanly.