Free calculators and design tools for planning your marine or RV electrical system. Built by technicians, for boat and RV owners.
Calculate the correct wire gauge for your circuits based on current draw, cable length, and acceptable voltage drop.
Determine the right battery bank capacity based on your loads, usage patterns, and desired autonomy.
Design and document your electrical system with our visual wiring diagram tool. Drag-and-drop components with smart wire routing.
These tools are designed by working marine and RV technicians who understand the practical challenges of electrical system design. Whether you're planning a simple battery upgrade or a complete rewire, our calculators help you get the details right the first time.
All calculations follow industry standards including ABYC guidelines for marine applications. However, these tools are for planning purposes — always have a qualified technician review your designs before installation.
Use the calculators to size the system, then book a consult and we'll design and install it.
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