Boat Wiring Diagram

Wire your boat right the first time. Boat Wiring Diagram builds a complete DC wiring diagram for your boat from a few simple choices — and sizes every wire and fuse for you. PICK, DON'T DRAW Follow 7 short steps: boat type, batteries, battery switch, engine and trolling motor, charging, add-ons. The diagram redraws as you go. Options that don't fit your setup are greyed out with the reason why. EVERY WIRE AND FUSE SIZED Wire gauges follow ABYC E-11 voltage-drop and ampacity rules (3% for critical circuits, 10% for the rest). Every wire on the diagram is numbered, color-coded and listed with its gauge, current, run length and voltage drop. Each circuit gets the right fuse or breaker. 30+ ADD-ONS WITH REAL PRODUCTS Nav lights, bilge pumps with auto float switch, fish finders and forward-facing sonar, VHF, stereo and amps, livewells, shallow-water anchors, windlass, trim tabs, inverters, battery monitors and more — with typical current draws from real products. BATTERIES, SWITCHES AND CHARGING 12V or 24V, start and house banks, flooded / AGM / lithium, 1-2-BOTH switches, dual-circuit switches, ACR or DC-DC chargers, 12/24/36V trolling motor banks, onboard chargers, shore power and solar. LIVE SIMULATOR Turn the battery switch, start the engine, switch on equipment and watch current flow along the wires. Plug in shore power, add sunshine, flood the bilge, cause a short circuit and see the right fuse blow. Speed up time to see how long your batteries last. MEASURE ON A PHOTO OF YOUR BOAT Add a photo, set the boat length, and drag each part to where it's mounted. Cable runs are measured along the hull and used to size the wires. PARTS LIST AND CHECKS Get the full parts list with wire footage, plus design checks and install tips. SHARE IT Share the diagram as a picture or vector file, print it, or send the project file to your mechanic. Works fully offline. No account, no ads, no tracking. Wire sizes are recommendations — confirm against each product's manual and have a qualified marine electrician check your finished installation.