Free PCB design tools

22 browser-based tools for real PCB work. Every calculator cites its standard. Every file you upload stays on your machine. No account, no email, no upload to our servers.

Viewers

1 tool

Drop a file, see the answer. Files stay in your browser.

GERBER_VIEWER
Free Online Gerber Viewer
Drop a Gerber ZIP. See copper, silkscreen, drills, and traces in your browser. No sign-up, files never leave your device.

Generators

2 tools

Produce a real artefact (KiCad, CSV, JSON) you can download and use.

FOOTPRINT_GENERATOR
IPC-7351 Footprint Generator (KiCad)
Generate an IPC-7351 compliant PCB footprint from body/pad dimensions. Downloads as a KiCad `.kicad_mod` file. No AI, no upload, no signup.
per IPC-7351B
BOM_FORMATTER
BOM Formatter & Deduplicator
Paste or upload a messy CSV bill-of-materials. Get a clean, grouped, deduplicated BOM ready for JLCPCB, Digi-Key, or Mouser.

Calculators

15 tools

IPC-standard formulas. Cited, guarded, and unit-tested.

OHMS_LAW_CALCULATOR
Ohm's Law Calculator
Solve for voltage, current, resistance, or power instantly. Enter any two — get the other two.
RESISTOR_COLOR_CODE_CALCULATOR
Resistor Color Code Calculator (4/5/6-Band)
Decode or generate resistor color codes. Supports 4, 5, and 6-band resistors — bidirectional (colours → value or value → colours).
PCB_TRACE_WIDTH_CALCULATOR
PCB Trace Width Calculator (IPC-2221)
Minimum copper trace width for a given current + temperature rise, per IPC-2221. Supports internal and external layers, 0.5–3 oz copper.
per IPC-2221 §6.2
PCB_TRACE_RESISTANCE_CALCULATOR
PCB Trace Resistance & Voltage Drop Calculator
Resistance, voltage drop and power loss of a copper trace from its width, length, copper weight and temperature.
PCB_TRACE_SPACING_CALCULATOR
PCB Trace Spacing vs Voltage Calculator (IPC-2221)
Minimum spacing between conductors at a given voltage from IPC-2221B Table 6-1, for inner layers, bare outer layers and coated outer layers.
per IPC-2221B Table 6-1
VIA_CURRENT_CALCULATOR
Via Current Capacity Calculator (IPC-2152)
Max current for a plated-through-hole via, by barrel diameter, plating thickness, and allowed temperature rise.
per IPC-2152
PCB_VIA_PAD_SIZE_CALCULATOR
Via & Through-Hole Pad Size Calculator
Pad diameter, drill size and aspect ratio for vias and through-hole leads, including the diagonal rule for square header pins.
per IPC-2221 land formula
WIRE_GAUGE_CALCULATOR
Wire Gauge & Ampacity Calculator (AWG)
Find the right AWG wire for your current and voltage drop. Includes ampacity lookup and mm² cross-reference.
LED_RESISTOR_CALCULATOR
LED Series Resistor Calculator
Calculate the correct series resistor for any LED from supply voltage, forward voltage, and target current. Shows the nearest E-series value.
VOLTAGE_DIVIDER_CALCULATOR
Voltage Divider Calculator
Calculate output voltage from two resistors, or find the resistor pair that hits a target voltage. Nearest E-series match included.
MICROSTRIP_IMPEDANCE_CALCULATOR
Microstrip Impedance Calculator (IPC-2141)
Characteristic impedance for a trace on an outer layer above a ground plane, per IPC-2141.
per IPC-2141A
STRIPLINE_IMPEDANCE_CALCULATOR
Stripline Impedance Calculator (IPC-2141)
Characteristic impedance for a trace buried between two ground planes, per IPC-2141.
per IPC-2141A
DIFFERENTIAL_PAIR_CALCULATOR
Differential Pair Impedance Calculator
Differential and common-mode impedance for edge-coupled microstrip and stripline pairs (USB, Ethernet, LVDS).
CAPACITOR_CODE_CALCULATOR
Capacitor Code Decoder (SMD & Ceramic)
Decode 3-digit ceramic/SMD capacitor codes to capacitance, tolerance, and voltage rating.
PCB_COST_ESTIMATOR
PCB Cost Estimator (JLCPCB, PCBWay, OSH Park)
Estimate PCB fabrication cost by board size, layer count, quantity, and finish. Indicative pricing across major fabs.

Converters

2 tools

Bidirectional unit tools for PCB work.

MM_TO_MIL_CONVERTER
mm to mil Converter (PCB)
Convert millimetres to mils and back, with the trace widths and clearances the numbers actually map to.
MIL_TO_MM_CONVERTER
Mil to mm Converter for PCB Specs
Convert mils to millimetres one value at a time or a whole fab capability sheet at once, ready to type into metric design rules.

Reference

2 tools

Look-ups and planners for common design decisions.

PCB_STACKUP_PLANNER
PCB Layer Stackup Planner (2/4/6/8-Layer)
Plan a PCB layer stack with copper weights, dielectric heights, FR4 Dk values, and finished thickness — 2 to 8 layers.
CONNECTOR_PITCH_REFERENCE
Pin Header & Connector Pitch Reference
Quick-reference for pin header and connector pitches — 0.1", 2.0 mm, 2.54 mm, JST, Molex, Micro-USB, USB-C.