pulpCircuit lets you design a circuit board in your browser: you draw the schematic, move on to the board, let automatic placement and routing do the heavy lifting, then download a fabrication package ready to upload to a PCB manufacturer. It is built for makers, students and small teams who want to go from schematic to ordered board without installing anything.
Getting started
- Open pulpCircuit. The first time you open it, an example appears on its own so you can see what pulpCircuit looks like: the Site humidity sensor board (ESP32, humidity sensor, USB-C), placed and routed automatically in a few seconds, a good way to explore the four views, Schematic, Board, 3D and Fabrication. Start from scratch or Remove the example clears it in one click, and File › See the example again brings it back. Nothing is saved until you change it. The Examples menu also offers the 555 blinker and the ESP32 sensor board.
- To start from scratch, choose Examples › New blank project. In the Schematic view, search the Library (left panel) for a component, click it, then drop it on the sheet. R rotates it, X mirrors it, Esc stops placing.
- Connect pins with the Wire tool (W) or name nets with a Net label (L): two labels with the same name are connected, even without a wire. The GND, VCC, +5V and +3V3 buttons place power symbols.
- Click Go to board: references are numbered and the components appear below the board outline. Run Auto-place, then Auto-route, then Ground plane if your schematic has a GND net.
- Open the Fabrication view: once the DRC is clean and every connection is routed, the board is marked Ready to order and you can Download Gerber zip.
Common tasks
How do I import a KiCad project?
Choose File › Import a KiCad project… and select the .kicad_sch, the .kicad_pcb and, if needed, the .kicad_mod footprints together. You can also drop several files onto the window. A summary lists how many components, nets, tracks, vias and zones were imported, and what is missing (footprints to import, skipped sub-sheets, skipped inner cutouts).
How do I check my schematic?
The ERC button opens the list of electrical errors: unconnected pin, isolated net, conflicting outputs, power input with no source, dangling wire, duplicate or unnumbered reference, missing footprint. Click Annotate to number references. The status bar always shows “ERC clean” or the error count.
How do I simulate the circuit?
Click Simulate in the Schematic view. Choose DC (operating point) or Transient (behaviour over time), set the Supplies and the Duration, then press Play: LEDs light up on the schematic. The built-in simulator handles resistors, capacitors, inductors, diodes, LEDs, transistors, regulators and the 555 timer. Microcontrollers, sensors and op-amps are not simulated: they are left open and listed as ignored.
How do I prepare the bill of materials (BOM)?
In each component's properties, fill in Value, Footprint, Manufacturer part number and Manufacturer, or tick Do not populate. The BOM tab groups identical lines with their references and quantity. In Fabrication, BOM and CPL (component positions) are available in JLCPCB and PCBWay formats; for JLCPCB, also fill in the parts' LCSC numbers.
How do I see my board in 3D?
The 3D view shows the assembled board (Perspective, Top, Bottom, components shown or hidden). The glTF and STL buttons export a 3D model from it.
How do I print the schematic?
File › Print schematic (Ctrl+P in the Schematic view) prints it in A4 landscape.
How do I route a track by hand?
In the Board view, choose Route a track (X) and click a pad. While drawing, V drops a via and switches layer, and / flips the direction of the bend. B toggles the active layer between top and bottom. Hold Alt for a fine 0.05 mm step.
How do I set the design rules?
The Classes panel (Net classes button) sets track width, clearance and via size for each class; click nets to assign them. In the board properties, Manufacturer capabilities applies conservative values for JLCPCB, PCBWay, OSH Park, or Conservative (any manufacturer). Always double-check these values on the manufacturer's website.
How do I change the board shape?
In the board properties, pick Rectangle (rounded corners) and its dimensions, or Free shape (draw it) and draw it with Free outline (double-click to close it). The same panel sets the thickness, 2 or 4 copper layers, the solder mask colour and the finish (HASL or ENIG). The Mounting hole, Keep-out area, Text and Measure tools complete the layout.
How do I order my board?
In Fabrication, the Order my board section walks you through the steps. Download the Gerber zip (do not unzip it) and, for assembly, the BOM and CPL files. The buttons open the JLCPCB or PCBWay quote page in a new tab, where you upload the zip yourself. pulpCircuit never orders or pays for anything on your behalf.
How do I design an enclosure or program the board?
In Fabrication, Design the enclosure in pulpCase sends the board (outline, holes, connectors, heights) to pulpCase. File › Export board for an enclosure (.pboard) produces the same file, which pulpRobot accepts as a part and pulpLab turns into pin constants (pins.h or pins.py) when the board carries an ESP32, RP2040, ATmega328P or ATtiny85.
Supported formats
| Format | Open | Save | Notes |
|---|---|---|---|
| pulpCircuit (.pcircuit) | Yes | Yes | Lossless native format. |
| KiCad schematic (.kicad_sch) | Yes (import) | No | KiCad 6 to 9: symbols, values, footprints, wires, labels, no-connect flags. |
| KiCad board (.kicad_pcb) | Yes (import) | No | Components, nets, tracks, vias, zones and outline. |
| KiCad footprint (.kicad_mod) | Yes (import) | No | Added to the project, original attribution kept. |
| Netlist (.net, KiCad format) | No | Yes (export) | File › Export netlist. |
| Gerber RS-274X (X2) and Excellon drill | Yes (checking) | Yes | Fabrication zip; Check Gerber files… opens a zip or loose files in the viewer. |
| BOM and CPL (CSV) | No | Yes | JLCPCB and PCBWay column layouts. |
| Board exchange file (.pboard) | No | Yes | For pulpCase, pulpRobot and pulpLab. |
| 3D model (.glb, .stl) | No | Yes | From the 3D view of the assembled board. |
Known limitations:
- pulpCircuit does not write .kicad_sch or .kicad_pcb files: exchange with KiCad is one-way, apart from the netlist.
- Legacy KiCad 5 schematics (.sch) are not read.
- Hierarchical sub-sheets are not imported (main sheet only) and inner board cutouts are ignored.
- Footprints missing from an imported schematic must be supplied as .kicad_mod files.
- 2 or 4 copper layers only.
- On a dense board, automatic routing may leave some connections unrouted: the DRC lists them so you can finish by hand.
- The Gerber viewer ignores step-and-repeat (SR) blocks and some transformations, and says so in the syntax check.
Keyboard shortcuts
| Shortcut | Action |
|---|---|
| Ctrl+S | Save |
| Ctrl+Shift+S | Save as |
| Ctrl+O | Open |
| Ctrl+Z | Undo |
| Ctrl+Y or Ctrl+Shift+Z | Redo |
| Ctrl+P | Schematic view: print the schematic (A4 landscape) |
| V | Schematic: Select tool |
| W | Schematic: Wire tool |
| L | Schematic: net label |
| Q | Schematic: no-connect flag |
| G / P | Schematic: place a ground / power symbol |
| R (Shift+R the other way) | Rotate the selection or the part being placed |
| X | Schematic: mirror; Board: Route a track tool |
| F | Schematic: fit the view; Board: flip the part to the other side |
| L | Board: lock or unlock the part |
| B | Board: switch the active layer |
| V | Board, while routing: via and layer change |
| / | Flip the bend direction while drawing |
| Alt (hold) | Board: fine 0.05 mm step |
| Del | Delete the selection |
| Esc | Stop the current tool, clear the selection |
| Home | Fit the view |
| Space + drag, right-drag or mouse wheel | Pan, zoom |
On a Mac, use Cmd instead of Ctrl. Ctrl+J opens pulpAssist and Ctrl+Shift+O the open documents panel.
AI in pulpCircuit
pulpCircuit does not use an AI model. Automatic placement, automatic routing, the checks and the simulation are conventional algorithms that run on your device.
If you have set up pulpAssist, the assistant can read the open project (components, nets, check results), add a component, connect pins to a net, or start placement and routing. Every change is shown to you before it is applied, and can be undone in one step with Ctrl+Z. The project content is then sent to the service you configured for the assistant. Always review the schematic and run the ERC and DRC again afterwards.
FAQ and troubleshooting
Where are my projects stored?
On this device, in the space reserved for the browser, with a recovery draft saved automatically; clearing the browser's data erases them. To keep a copy on disk, use File › Save (.pcircuit format). See documents and backups and work folder.
My KiCad import says “Footprint not found”. What should I do?
The schematic references footprints that are not in the file. Import the matching .kicad_mod files (File › Import KiCad footprints) or choose another footprint in the component properties. Importing the .kicad_pcb as well also fixes it, since it contains the placed footprints.
If I save after a KiCad import, is my KiCad file changed?
No. The imported project is saved in .pcircuit format under a new name you choose; your KiCad files stay untouched.
Auto-route did not route everything.
Try again after a new Auto-place, enlarge the board, switch to 4 layers or reduce the track width in the net classes (without going below the manufacturer's capabilities). Route the remaining connections by hand with X.
The 3D view stays blank.
It needs a recent graphics card and a compatible browser. Turn on hardware acceleration or try another recent browser (Chrome or Edge).
Does pulpCircuit work offline?
Yes, once the app has loaded. The 3D view needs a first load, so open it once while online. Only the manufacturers' websites need a connection.
The manufacturer rejects my files.
Open the downloaded zip with Check Gerber files…: the viewer reads it the way the manufacturer will, and the syntax check flags anything unusual. Also make sure the capabilities you chose match the service you are ordering.