Free · No signup to start
Design your off-grid solar system without guessing.
Answer a few plain-English questions and get a complete, code-aware parts list — the right battery bank, inverter, charge controller, and panels for your build. Then fine-tune every component in the Deep Toolbox. All of it free.
No account, no paywall, no email required to use the tools. Share your build with one link.
Three free tools
Each one stands alone. Together they take you from "I have no idea" to a build you can buy.
System Sizing Wizard
The beginner path. Tell it what you're powering and where, and it sizes the whole system for you — silently handling voltage tiers, autonomy, roof limits, and NEC-2023 wiring math.
Size my system →Deep Toolbox
The builder path. Every component, every dropdown, unfiltered. Swap parts, compare options, and see cost and wiring update live. Your finished build is one shareable link.
Open the toolbox →Load Architect
Not sure how much power you actually need? Build your daily load profile appliance by appliance and get a real watt-hour number to feed into the wizard.
Calculate my load →How it works
Most people are done in ten minutes.
Add up your loads in the Load Architect (or bring your own number).
Run the Wizard. It recommends a complete, buyable system sized to your loads, location, and roof.
Fine-tune in the Toolbox if you want, then buy the parts from the linked retailers.
Free video masterclass
The whole off-grid build, start to finish — sizing, wiring, safety, and installation. No cost, no gate.
Watch the masterclass →Free downloads
The Beginner Solar Blueprint and the Technical Toolkit — the same PDFs early builders paid for.
Get the free PDFs →Questions
Is this really free?
Yes. The wizard, toolbox, load calculator, masterclass, and PDFs are all free. Beginner Solar earns a commission if you buy components through the retailer links in a build — that's the only way the site makes money, and it never changes what the tools recommend.
Do I have to sign up?
No. The tools work with no account. We only ask for an email if you want a PDF emailed to you or your parts list sent to your inbox.
How do you make money if it's free?
Affiliate commissions on the components you choose to buy, from established retailers. See our affiliate disclosure.
Is the wiring math trustworthy?
The engine is built to NEC-2023 conventions and is deliberately conservative — it fails closed rather than recommending something unsafe. It is a design aid, not a substitute for a licensed electrician or your local code authority.