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Qucs-S

Circuit simulator GUI using ngspice, Xyce and other engines

★ Stars1.4k1,409 on GitHub
Last commit17 Oct 2026
LicenceGPL-2.0SPDX, from the repository
View on GitHub ↗

From GitHub, fetched 19 Oct 2026.

Visit ra3xdh.github.io ↗

Qucs-S is a free circuit simulation program with a schematic editor that drives SPICE-compatible engines such as ngspice and Xyce, for DC, AC, transient and RF analysis.

Fit: files and licence

Runs onWindows, macOS, Linux
Commercial useAllowed
Open-source licence (GPL-2.0): the Open Source Definition rules out restrictions on fields of use, including business use.

Sources: opensource.org/osd. “Runs on” is from this listing. Blank means we haven't found it in official docs yet, not that it's unsupported.

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