circuit-to-svg

August 18, 2026 · View on GitHub

A TypeScript library for converting Circuit JSON to Schematic, PCB and Assembly SVG representations.

Getting Started Contributor Video

PCB Schematic
npm add circuit-to-svg
# or...
bun add circuit-to-svg

Overview

This library provides functionality to convert Circuit JSON into SVG (Scalable Vector Graphics) representations. It supports both schematic and PCB (Printed Circuit Board), and Assembly layouts.

Installation

npm install circuit-to-svg

Usage

import { readFileSync, writeFileSync } from 'fs'
import { convertCircuitJsonToSchematicSvg } from 'circuit-to-svg'

const circuitJson = JSON.parse(readFileSync('circuit.json', 'utf8'))
const schematicSvg = convertCircuitJsonToSchematicSvg(circuitJson)

writeFileSync('schematic.svg', schematicSvg)

Explore the API sections below to render PCB, assembly, pinout, simulation, and solder paste views.

FunctionDescription
convertCircuitJsonToSchematicSvgGenerate schematic SVG output from Circuit JSON.
convertCircuitJsonToSchematicSimulationSvgOverlay simulation data on schematic diagrams.
convertCircuitJsonToPcbSvgRender PCB layouts as SVG graphics.
convertCircuitJsonToSolderPasteMaskCreate solder paste mask layers for fabrication.
convertCircuitJsonToAssemblySvgProduce assembly view SVGs for board visualization.
convertCircuitJsonToPinoutSvgBuild annotated pinout diagrams for boards and modules.
convertCircuitJsonToSimulationGraphSvgPlot simulation experiment results as SVG graphs.

API

convertCircuitJsonToSchematicSvg

convertCircuitJsonToSchematicSvg(circuitJson: AnyCircuitElement[], options?): string

Converts a schematic circuit description to an SVG string.

import { convertCircuitJsonToSchematicSvg } from 'circuit-to-svg'

const schematicSvg = convertCircuitJsonToSchematicSvg(circuitJson, {
  includeVersion: true,
})

Schematic grid snapshot

Options

  • width and height – dimensions of the output SVG. Defaults to 1200x600.
  • grid – enable a schematic grid (true) or configure cell size and labels.
  • labeledPoints – annotate specific coordinates with helper labels.
  • colorOverrides – override portions of the schematic color palette.
  • className – add one or more extra classes to the root schematic <svg>.
  • css – append custom CSS to the generated schematic SVG.
  • includeVersion – if true, add a data-circuit-to-svg-version attribute to the root <svg>.

convertCircuitJsonToPcbSvg

convertCircuitJsonToPcbSvg(circuitJson: AnyCircuitElement[], options?): string

Converts a PCB layout description to an SVG string.

import { convertCircuitJsonToPcbSvg } from 'circuit-to-svg'

const pcbSvg = convertCircuitJsonToPcbSvg(circuitJson, {
  matchBoardAspectRatio: true,
  backgroundColor: '#1e1e1e',
  showPinNumbers: true,
})

PCB default snapshot

Options

  • width and height – dimensions of the output SVG. Defaults to 800x600.

  • matchBoardAspectRatio – if true, adjust the SVG dimensions so the resulting aspect ratio matches the pcb_board found in the circuit JSON.

  • backgroundColor – fill color for the SVG background rectangle. Defaults to "#000".

  • drawPaddingOutsideBoard – if false, omit the board outline and extra padding around it. Defaults to true.

  • showPcbNotes – if false, hide all pcb_note* overlay primitives at render time. Defaults to true.

  • showPinNumbers – if true, annotate PCB pads with small gray pin numbers. Defaults to false.

  • showSolderPaste – if true, render pcb_solder_paste primitives. Defaults to false.

  • shouldDrawErrors – if true, display visual error indicators (red diamonds with text) for error elements in the circuit JSON. Supports:

    • pcb_trace_error – errors related to PCB traces
    • pcb_footprint_overlap_error – errors for overlapping pads, plated holes, and holes (displays error indicators at each affected element with connecting lines)
    • pcb_pad_trace_clearance_error – clearance errors between pads and traces
    • pcb_via_trace_clearance_error – clearance errors between vias and traces

    Defaults to false.

  • shouldDrawWarnings – if true, display yellow component highlights and warning messages for supported warning elements in the circuit JSON. Supports pcb_connector_not_in_accessible_orientation_warning and pcb_manual_edit_conflict_warning. Defaults to false.

  • includeVersion – if true, add a data-circuit-to-svg-version attribute to the root <svg>.

convertCircuitJsonToAssemblySvg

Converts circuit JSON into an assembly view of the board and components.

import { convertCircuitJsonToAssemblySvg } from 'circuit-to-svg'

const assemblySvg = convertCircuitJsonToAssemblySvg(circuitJson, {
  includeVersion: false,
})

Assembly board snapshot

Options

  • width and height – dimensions of the output SVG. Defaults to 800x600.
  • includeVersion – if true, add a data-circuit-to-svg-version attribute to the root <svg>.

convertCircuitJsonToPinoutSvg

Generates pinout diagrams that call out ports, pads, and holes for boards or modules.

import { convertCircuitJsonToPinoutSvg } from 'circuit-to-svg'

const pinoutSvg = convertCircuitJsonToPinoutSvg(circuitJson)

Pinout snapshot

Options

  • width and height – dimensions of the output SVG. Defaults to 800x600.
  • includeVersion – if true, add a data-circuit-to-svg-version attribute to the root <svg>.

convertCircuitJsonToSchematicSimulationSvg

Overlays simulation results directly on the rendered schematic for easy debugging.

import { convertCircuitJsonToSchematicSimulationSvg } from 'circuit-to-svg'

const schematicSimulationSvg = convertCircuitJsonToSchematicSimulationSvg({
  circuitJson,
  simulation_experiment_id: 'simulation-experiment-id',
  simulation_transient_current_graph_ids: ['transient-current-graph-id'],
  simulation_transient_voltage_graph_ids: ['transient-graph-id'],
  schematicHeightRatio: 0.6,
})

Schematic simulation snapshot

Options

  • width and height – overall SVG dimensions. Defaults to 1200x1200.
  • schematicHeightRatio – ratio of the SVG dedicated to the schematic view. Defaults to 0.55.
  • schematicOptions – forward additional schematic rendering options (except width, height, and includeVersion).
  • simulation_transient_current_graph_ids – optional list of current graph IDs to render.
  • simulation_transient_voltage_graph_ids – optional list of voltage graph IDs to render.
  • includeVersion – if true, add a data-circuit-to-svg-version attribute to the root <svg>.
  • graphAboveSchematic – if true, place the simulation graph above the schematic instead of below (defaults to false).

convertCircuitJsonToSimulationGraphSvg

Creates standalone graphs for circuit simulation experiments.

import { convertCircuitJsonToSimulationGraphSvg } from 'circuit-to-svg'

const simulationGraphSvg = convertCircuitJsonToSimulationGraphSvg({
  circuitJson,
  simulation_experiment_id: 'simulation-experiment-id',
  simulation_transient_current_graph_ids: ['transient-current-graph-id'],
  simulation_transient_voltage_graph_ids: ['transient-graph-id'],
})

Simulation graph snapshot

Options

  • width and height – SVG dimensions for the graph. Defaults to 1200x600.
  • simulation_transient_current_graph_ids – optional list of current graph IDs to render.
  • simulation_transient_voltage_graph_ids – optional list of voltage graph IDs to render.
  • includeVersion – if true, add a data-circuit-to-svg-version attribute to the root <svg>.

convertCircuitJsonToSolderPasteMask

convertCircuitJsonToSolderPasteMask(circuitJson: AnyCircuitElement[], options: { layer: 'top' | 'bottom'; width?; height?; includeVersion? }): string

Produces top and bottom solder paste mask renderings suitable for stencil generation.

import { convertCircuitJsonToSolderPasteMask } from 'circuit-to-svg'

const solderPasteMaskSvg = convertCircuitJsonToSolderPasteMask(circuitJson, {
  layer: 'top',
})

Solder paste snapshot

Options

  • layer'top' | 'bottom', chooses which solder paste layer to render. Defaults to 'top'.
  • width and height – dimensions of the output SVG. Defaults to 800x600.
  • includeVersion – if true, add a data-circuit-to-svg-version attribute to the root <svg>.