Introduction

Spice++ is a SPICE circuit simulator in the browser, with an assistant that builds circuits, runs the analysis and checks the result against your spec.

The editor runs in the browser. Simulation happens on your own computer, so there is nothing to install and nothing waits in a queue.

What it does

Schematic capture with generic parts and real named parts such as the LM358, 2N3904 and 1N4148. See Parts library.
Operating point, DC sweep, transient, AC and noise analyses, with parameter and temperature sweeps. See Analyses.
An assistant that builds on the canvas through the same actions you would take, measures your targets from a simulation and repairs a design that misses. See Working with the assistant.
Import from LTspice, KiCad, SPICE netlists and Falstad, and export images, netlists, Verilog and a bill of materials. See Import and export.
Sharing by email or link with four roles, comments and live presence. See Sharing.

How these docs are organized

Start here: Your first circuit and the keyboard shortcuts.
Simulation: Every analysis and directive, with syntax and examples.
Parts and models: The parts library, source waveforms, model cards and subcircuits.
Files: What imports, what exports, and what carries over.
The assistant: Modes, models and credits, spec checks, and what it can automate.
Collaboration: Roles, invitations, share links, comments and presence.
Account and billing: Settings, plans, cancelling, and single sign-on.