Free Victron System Calculators & Tools

Plan your Victron energy system with confidence. Our free calculators cover cable sizing, voltage drop, battery banks, solar yield, and fuse ratings — everything you need for a safe, efficient installation.

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Victron System Builder

Design a complete Victron energy system for your campervan, motorhome, boat, or off-grid cabin. Get personalised component recommendations with live UK pricing.

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Calculators

Individual tools for planning specific aspects of your installation

DC Voltage Drop Calculator

Calculate voltage drop across DC cable runs in your Victron energy system. Check if your wiring meets the recommended 3% threshold.

cables wiring voltage
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Battery Bank Sizing Calculator

Determine the right battery bank capacity based on daily consumption, autonomy days, and depth of discharge for lithium and lead-acid batteries.

batteries capacity lithium
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Solar Panel Yield Estimator

Estimate energy output from solar panels at any UK location. Get seasonal breakdowns and recommended Victron MPPT charge controllers.

solar panels MPPT
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Cable Sizing Guide

Find the minimum cable cross-section area for your DC installation. Enter current draw and cable length for the recommended cable size.

cables wiring CSA
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Fuse Sizing Calculator

Calculate the correct fuse or circuit breaker rating for your DC cables. Fuses protect cables from overheating and should be sized correctly.

fuses safety protection
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Victron AI Assistant

Ask any question about Victron products — specifications, sizing, installation, compatibility, and more. AI-powered answers from our comprehensive database.

AI assistant help questions
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Why Use Our Calculators?

Designed specifically for Victron Energy system installations

Safety First

Correctly sized cables and fuses prevent overheating, fire risk, and equipment damage. Our tools help you get it right the first time.

Victron-Optimised

Calculations are tuned for Victron equipment thresholds, including the 3% voltage drop recommendation for inverters and chargers.

Works Everywhere

All calculators run entirely in your browser. No app to install, no account required, and fully usable on mobile, tablet, or desktop.

Save Money

Right-sizing your components avoids overspending on oversized cables and batteries, or the costly mistakes of undersized parts.

Frequently Asked Questions

Are these Victron calculators free to use?

Yes, all calculators and tools on Victron for Less are completely free. They are designed to help you plan and optimise your Victron energy system without any cost.

Do I need to create an account to use the tools?

No account is required. All tools work directly in your browser with no sign-up or login needed.

Are the calculations accurate for Victron equipment?

Our calculators use industry-standard electrical formulas and are tailored for DC systems commonly used with Victron Energy products. They provide reliable estimates, though we always recommend consulting a qualified installer for critical installations.