Getting Started

The SPICE editor uses a three-column workspace: Components, Circuit editor, and Results. Build a schematic in the center, choose an analysis, and select browser or server execution in the Results panel.

Build a circuit

Select a component in the left panel, then click the canvas to place it.
Place Ground and connect component terminals with the Wire tool.
Double-click a component to edit its label, value, and model where applicable.
Add voltage or current probes to record the quantities needed in the result.
Select an analysis and run locally or on the server.

Current component set

Group	Available editor components	Server simulation
Passives	Resistor, capacitor, polarized capacitor, and inductor	R, C, and L elements are supported.
Sources	Battery, DC/AC voltage source, and DC/AC current source	Independent V and I sources are supported.
Semiconductors	Diode, LED, Zener diode, NPN transistor, and PNP transistor	D and Q elements are supported with validated D, NPN, or PNP models.
Editor structure	Ground, wire, text, probes, transformer, center-tapped transformer, and subcircuit	Ground, wiring, and probes support compatible circuits. Transformer coupling and subcircuits are not accepted by the current server validator.

The local browser engine can run editor content outside the server subset when ngspice supports it. Check Limits & Imported Netlists before switching the same circuit to server mode.

Diode and BJT models

The current model selectors include:

Diodes: 1N4148, 1N914, 1N4007, 1N4001, and 1N5819.
LEDs: RED_LED, GREEN_LED, and BLUE_LED.
Zener diodes: 1N4733, 1N4728, and 1N4742.
NPN transistors: 2N3904 and 2N2222.
PNP transistors: 2N3906 and 2N2907.

NPN and PNP selectors show models with the matching polarity. You may instead provide a custom .model statement for a D, NPN, or PNP device. The selected model name is displayed next to the schematic symbol and is validated again before a server run.

Choose an execution mode

Browser simulation

Select Run locally. ngspice runs in WebAssembly in the browser and no account is required. Use this path for fast local work and for the browser-only analysis overlay commands.

Server simulation

Select Run on Giux-CalcLab server. Sign in, create an account, or continue as a verified guest. Guest verification uses an email OTP; after verification, a separate temporary capability authorizes one job. The server validates the circuit and executes one bounded analysis in an isolated worker.

Read the result

The Results panel reports job status and provides the quick result, SPICE Log, downloads, and the Waveform Viewer. Server results are temporary until an eligible Registered or Trusted user selects Keep result.