- Home
- Physics Simulation Software
- ngspice
ngspice
What it is
ngspice is a free, open-source simulator for electric and electronic circuits. It works with analog, digital, and mixed-signal designs described in netlists, using models for active, passive, analog, and digital elements. Model parameters can come from collections, manufacturers, or foundries, and SPICE compatibility supports PSPICE or LTSPICE device model parameters and netlists for discrete circuits. Mixed-signal co-simulation supports Verilog blocks compiled with Verilator and, since ngspice-44, VHDL blocks using GHDL. The OSDI/OpenVAF interface integrates Verilog-A compact device models without requiring programming on the ngspice side. The software can also be compiled as a shared library or DLL for control by another application. Integrations include KiCad, Autodesk Fusion, and Python interfaces such as PySpice. It runs on Linux, macOS, and Windows, but has no schematic entry: input is command-line or file-based. The stable download page offers source archives and Windows binaries; Linux users are directed to their distributor or source compilation, and the project's own macOS release is unavailable there.
For and against
For
- Free and open-source circuit simulation
- Supports analog, digital, and mixed-signal circuits
- SPICE compatibility for discrete circuits
- Integrates with KiCad and Autodesk Fusion
Against
- No schematic entry
- Input is command-line or file-based
- Project macOS release unavailable on stable download page
The verdict
ngspice offers circuit simulation with support for multiple signal types, model integrations, and application connections. Users must provide netlists rather than create schematics in the software.
Who it suits
It suits people working with circuit netlists who need analog, digital, or mixed-signal simulation. Its integrations and library options may also suit users connecting circuit simulation to other applications.
Plans and prices
ngspice
Circuit simulator; command-line or file-based input; no schematic entry
Read 7 Oct 2026 · ngspice.sourceforge.io
On the record
- Circuit types
- It simulates analog, digital, and mixed-signal circuits described in netlists.ngspice.sourceforge.io · read 7 Oct 2026
- Compatibility
- It is SPICE-compatible and can use PSPICE or LTSPICE device model parameters and netlists for discrete circuits.ngspice.sourceforge.io · read 7 Oct 2026
- Downloads
- The stable download page offers source archives and Windows binaries, while noting that Linux users should use their distributor or compile from source and that its own macOS release is currently unavailable there.ngspice.sourceforge.io · read 7 Oct 2026
- Input limitation
- ngspice does not provide schematic entry; its input is command-line or file-based.ngspice.sourceforge.io · read 7 Oct 2026
- Mixed-signal integration
- It supports mixed-signal co-simulation with Verilog blocks compiled using Verilator and, since ngspice-44, VHDL blocks using GHDL.ngspice.sourceforge.io · read 7 Oct 2026
- Model integration
- The OSDI/OpenVAF interface integrates Verilog-A compact device models without requiring programming on the ngspice side.ngspice.sourceforge.io · read 7 Oct 2026
- Models
- It provides device models for active, passive, analog, and digital elements, and can use model parameters from collections, manufacturers, and foundries.ngspice.sourceforge.io · read 7 Oct 2026
- Programming
- ngspice can be compiled as a shared library or DLL for control by a calling application.ngspice.sourceforge.io · read 7 Oct 2026
- Purpose
- ngspice is an open-source simulator for electric and electronic circuits.ngspice.sourceforge.io · read 7 Oct 2026
- Support
- The project offers mailing lists, discussion forums, a bug tracker, an FAQ, and documentation.ngspice.sourceforge.io · read 7 Oct 2026
- Third-party integrations
- The project lists integrations with KiCad, Autodesk Fusion, and Python interfaces including PySpice.ngspice.sourceforge.io · read 7 Oct 2026
