Import and export

Open LTspice, KiCad, SPICE and Falstad circuits in Spice++, and export SVG, PNG, netlists, Verilog, a bill of materials and waveform data.

Use the import and export buttons in the top bar. The format is detected from the file extension, or you can choose it.

Schematic formats

FormatExtensionsImportExport
Spice++ document (Volt JSON).volt.json .jsonYesYes
SPICE netlist.cir .net .sp .ckt .spiceYesYes
LTspice schematic.ascYesYes
KiCad 6 and later.kicad_schYesYes
Falstad / CircuitJStext or linkYesNo
SVG.svgNoYes
PNG at 2× resolution.pngNoYes
Verilog, structural.vNoYes
Bill of materials.bom.csvNoYes

What carries over

Spice++ documents
Exact round trips.
SPICE netlists
Keep the circuit but have no drawing, so imports are laid out automatically, with a net label on each named net.
LTspice and KiCad
Keep both placement and connections for every part Spice++ knows. Parts it does not know arrive as labelled placeholders with a warning rather than being dropped.
Falstad
Paste a circuit as text or as a falstad.com link; compressed links are decoded.
Verilog
Describes connectivity only, for checks in tools such as Yosys.

Waveform data

FormatExtensionImportExport
CSV.csvYesYes
LTspice and ngspice raw.rawYesYes

Imported waveforms open in the waveform panel next to your own results, so you can compare a measurement or another simulator's output against Spice++.