liminfoKiCad Reference
Free reference guide: KiCad Reference
About KiCad Reference
The KiCad Reference is a comprehensive, searchable cheat sheet for KiCad, the open-source electronics design automation (EDA) suite used for schematic capture and PCB layout. It covers the complete schematic editor workflow including symbol placement (A), power port placement (P), wire drawing (W), net labeling (L, Ctrl+L for global labels), symbol property editing (E, V, F), automatic annotation, and Electrical Rules Check (ERC) for detecting unconnected pins, driver conflicts, and pin type incompatibilities.
The PCB editor section documents essential routing commands: track routing (X) with angle toggles and via insertion, copper zone filling (B) for GND planes, interactive router modes (Push & Shove, Walkaround, Highlight Collisions), via types (through-hole, blind, buried, micro), and component manipulation (M for move, R for rotate, F for layer flip). Design rules coverage includes clearance settings, net classes for differential pairs and power tracks, DRC checks, and IPC-2221 track width calculations for current capacity from 0.5A to 10A.
This reference also covers the PCB layer stack including copper layers (F.Cu, B.Cu, In1.Cu, In2.Cu for 4-layer boards), silkscreen (F.SilkS, B.SilkS), solder mask (F.Mask, B.Mask), and board outline (Edge.Cuts). Output and fabrication sections detail Gerber file generation with proper extensions (.gtl, .gbl, .gts, .gbs, .gto, .gm1), Excellon drill files, BOM export with manufacturer part number fields, SMT pick-and-place coordinate files, and 3D viewer usage.
Key Features
- All schematic editor shortcuts: symbol placement (A), power symbols (P), wiring (W), labeling (L), properties (E/V/F), annotation, and ERC
- PCB routing commands with track drawing (X), copper fill (B), interactive router modes (D), via insertion (V), and drag-with-traces (G)
- Design rule configuration: clearance rules, net classes for signal groups (default, power, USB differential, high voltage), and DRC checks
- IPC-2221 track width calculator reference for current capacity from 0.5A (0.2mm) through 10A (4.5mm) on 1oz copper
- Complete layer stack documentation: copper, silkscreen, solder mask, fabrication, courtyard, and Edge.Cuts board outline
- Gerber export guide with all required file extensions, Excellon drill format, and manufacturing-ready output checklist
- BOM and pick-and-place export with reference, value, footprint, manufacturer, MPN, and X/Y coordinate fields
- Footprint editor basics, 3D viewer controls, and custom pad pattern creation for SMD and through-hole components
Frequently Asked Questions
What is the KiCad Reference and who is it for?
The KiCad Reference is a free, browser-based quick-reference for KiCad EDA software covering schematic capture and PCB layout shortcuts, design rules, layer management, and fabrication output. It is designed for electronics engineers, PCB designers, hobbyists, and students who need instant access to KiCad commands without switching away from their design work.
What are the most important KiCad schematic editor shortcuts?
The essential schematic shortcuts are: A (place symbol), P (place power symbol), W (draw wire), L (place net label), Ctrl+L (global label), E (edit properties), V (edit value), F (assign footprint). After placing components, run Annotate (Tools > Annotate Schematic) to assign reference designators, then ERC (Inspect > Electrical Rules Checker) to verify connections before proceeding to PCB layout.
How do I set up design rules and net classes in KiCad?
Go to Board Setup > Design Rules > Net Classes. Create classes like Default (track 0.2mm, clearance 0.2mm), Power (track 0.5mm, clearance 0.3mm), and USB_DP (track 0.15mm for 90-ohm differential impedance). Assign nets to their respective classes. For via settings, typical values are 0.3mm drill with 0.6mm pad diameter. Use the DRC checker to verify all rules are met before generating manufacturing files.
What is the difference between Push & Shove, Walkaround, and Highlight Collisions routing modes?
These are KiCad interactive router modes accessed via the D shortcut or Route menu. Highlight Collisions simply shows where your trace conflicts with existing copper without moving anything. Walkaround automatically routes around existing tracks and obstacles. Push & Shove actively displaces existing traces to make room for your new route while maintaining design rule compliance. Push & Shove is generally preferred for dense boards.
What Gerber files do I need for PCB manufacturing?
For a standard 2-layer PCB, you need: F.Cu.gtl (front copper), B.Cu.gbl (back copper), F.Mask.gts (front solder mask), B.Mask.gbs (back solder mask), F.SilkS.gto (front silkscreen), Edge.Cuts.gm1 (board outline), and a .drl drill file in Excellon format. For 4-layer boards, add inner copper layers. Generate via File > Fabrication Outputs > Gerbers, and verify with a Gerber viewer before submitting to your fabrication house.
How do I calculate the correct track width for a given current?
Use the IPC-2221 standard as a reference. For outer layers with 1oz copper: 0.5A needs 0.2mm, 1A needs 0.3mm, 2A needs 0.7mm, 3A needs 1.0mm, 5A needs 2.0mm, and 10A needs 4.5mm. Inner layers require approximately 50% wider tracks due to reduced heat dissipation. KiCad includes a PCB Calculator tool, or you can use external IPC-2221 calculators for precise values accounting for temperature rise and copper weight.
How should I set up a 4-layer PCB stack-up in KiCad?
A typical 4-layer stack uses: F.Cu for signal and components, In1.Cu as a continuous GND plane, In2.Cu as a power plane, and B.Cu for signal and components. The solid ground plane on In1.Cu provides excellent signal integrity and EMI shielding. Create the GND plane by drawing a copper zone on In1.Cu, assigning it to the GND net, and pressing B to fill. Set up the layer count in Board Setup > Board Stackup.
What is included in BOM and pick-and-place export files?
The BOM (Bill of Materials) generated via Tools > Generate BOM includes Reference (R1, C1, U1), Value (10k, 100nF), Footprint, Manufacturer, MPN (manufacturer part number), Quantity, and Description fields. The pick-and-place file from File > Fabrication Outputs > Component Placement contains Reference, Value, Package, X/Y coordinates in mm, Rotation angle, and Side (top/bottom) for each component, used by SMT assembly machines.