What We Do
SolarEvaluator builds free solar calculators that help homeowners and businesses answer the questions that matter before buying a solar system: how many panels do I need, what size battery bank, which inverter, and what will it actually cost over 10 years?
Our flagship Solar System Calculator walks you through the complete sizing process in five steps — from your appliance list or electricity bill to a finished system with panels, batteries, inverter, charge controller, and a lead-acid vs LiFePO4 cost comparison. No sign-up, no sales calls, no installer referral fees. Just the numbers.
Why We Built This
Most solar calculators on the internet are lead-generation forms disguised as tools. You enter your address, click “Calculate,” and instead of an answer you get a phone call from a salesperson. We built SolarEvaluator because we believe the person considering solar deserves real numbers first — before talking to anyone.
Our calculators use real engineering: depth-of-discharge adjusted battery sizing, motor startup surge analysis for inverter selection, round-trip efficiency losses, and honest 10-year cost modeling that includes battery replacements. These are the same methods professional system designers use, made accessible to anyone with a browser.
Independent and Ad-Supported
SolarEvaluator is not affiliated with any solar panel manufacturer, battery brand, inverter company, or installation service. Our calculators do not favor any product or brand. We are funded through advertising (Google AdSense), which allows us to keep every tool completely free to use.
Our Tools
We are building a growing library of solar and electrical calculators, each designed as a standalone tool targeting a specific sizing question while linking together into a comprehensive toolkit. Our current and planned tools include the Solar System Calculator (live), Battery Backup Calculator, Solar Panel Output Calculator, kVA to Watts Converter, and Electrical Unit Converter.
Accuracy and Responsibility
We take the accuracy of our tools seriously. Our calculator engine accounts for system losses, battery depth of discharge, inverter efficiency, and charge controller safety margins. However, our tools provide estimates for planning purposes — they are not engineering designs. Real systems depend on site-specific factors like roof condition, shading, local codes, and equipment specifications that no online calculator can assess. Always confirm with a qualified installer before purchasing. See our Disclaimer for full details.
Contact
Have a question, suggestion, or correction? We want to hear from you. Reach us through our contact page or email us at hello@solarevaluator.com.