Hardware-accurate circuit simulation with a real SPICE engine and an AI that sees your breadboard. Know what's wrong before you touch the iron.
Built on tools engineers actually rely on. Every model traces back to a datasheet or a measured hardware result.
Place components on a 30×10 hole board with real 3D models from GrabCAD and SnapEDA. Every pin mapped, every node tracked.
Real ngspice 45.2 processes your netlist in <100ms. DC operating point, transient, AC frequency response — not approximation.
The AI sees your circuit via screenshot. Explain faults, suggest fixes, or build an entire circuit from a single text prompt.
Click to place resistors, LEDs, transistors on a virtual breadboard. Every hole numbered, every connection validated in real time.
One click sends your circuit to ngspice 45.2. DC, transient, AC frequency response — all processed in under 100ms.
Probe with the DMM, watch waveforms on the oscilloscope, ask the AI what's wrong. Fix it in sim — not on the bench.
The DMM and oscilloscope aren't afterthoughts. They're first-class instruments built directly into the simulation loop.
AI-powered and vision-enabled. It reads your breadboard layout, understands your components, and speaks in SPICE.
Cirq validates every circuit before and after each simulation. Shorts, overcurrent, floating nodes — flagged before you ever power up.
A wire creates a direct short between power and ground. This will blow your supply and destroy components.
No current-limiting resistor on D1. At 5V the LED draws 2.7× its rated maximum and will fail within seconds.
All nodes connected, current within limits, no floating pins. Circuit is safe to run through ngspice.
Simulation results measured against hardware and textbook theory. Not marketing claims — reproducible numbers.
Industry-standard device models. The same SPICE engine inside LTspice, HSPICE, and commercial EDA suites — running in your browser.
| Measurement | Cirq result | Theory / HW | Error |
|---|---|---|---|
| LED forward V | 1.89V | 1.86V | 0.9% |
| LED forward I | 14.16mA | 14.3mA | 0.98% |
| RC cutoff f_c | 1584.9Hz | 1592Hz | 0.45% |
| MOSFET V_GS | 2.45V | 2.5V | 2.0% |
| NPN I_C (w/ 470Ω) | 6.69mA | 6.58mA | 1.67% |
| NPN I_C (no R) | 80.89mA | 80mA limit | ⚠ danger |
Open the simulator. Build in 3D. Run SPICE. Know the answer before you pick up the soldering iron.