Solar & Energy Calculators
Eight calculators covering everything from your first savings estimate to full system sizing, ROI, and environmental impact — all free, all instant.
Why We Built These Calculators
Most solar calculators online ask for your name, email, and phone number before showing a single number — because they're lead-generation tools dressed up as calculators, built to hand your contact details to an installer. Every tool on this page works the opposite way: enter your numbers, get your answer, no signup, no sales call.
Each calculator is built around a specific decision you're actually trying to make, not a generic "solar quote." Start with the Savings Calculator if you're just curious what solar could do for your bill. Move to System Size and Cost once you're seriously considering it. Use ROI and the Grid Comparison to decide if the math works for your timeline. And if you're also thinking about backup power, Battery and Inverter sizing will get you real, usable numbers instead of a sales rep's rough guess.
Frequently Asked Questions
Are these solar calculators really free?
Yes, every calculator on PureEnergyTools is completely free with no account or signup required. We support the site through advertising and optional installer partner links, not by selling your contact information.
Which calculator should I start with?
If you're just exploring whether solar makes sense, start with the Solar Savings Calculator. If you're comparing quotes from installers, the System Size and Cost calculators will help you sanity-check what you're being offered.
Do I need to know technical details about solar to use these?
No. Every calculator only asks for information you can find on a utility bill or estimate reasonably — like your monthly bill amount or your city. Technical terms like peak sun hours and depth of discharge are handled automatically in the background.