Solar Calculators
Everything you need to plan a home solar project — payback, return on investment, loan payments, 2025 tax-credit eligibility, battery sizing and more. Every tool is free, shows its full formula, and runs on real 2026 government data.
Solar Payback Calculator
How many years until your panels pay for themselves, after state incentives (no federal credit for 2026 installs).
Most popular →Solar ROI Calculator
Your 25-year return on investment, total lifetime profit, and effective annual return.
Returns →Solar Loan Calculator
Monthly payment, total interest, and whether your savings beat your loan payment from day one.
Financing →Solar Financing Calculator
Compare cash, loan, lease and PPA in one view to find your cheapest path to solar.
Compare →Lease vs Buy Calculator
The true 25-year cost of leasing versus owning — including the home-value difference.
Decision →Solar Tax Credit Calculator
Check whether a 2025 install still qualifies for the 30% credit, and what changed for 2026.
2025 vs 2026 →Solar Battery Calculator
Size your home battery in kWh and decide whether backup storage earns its keep.
Storage →Solar Break-Even Calculator
The exact point your cumulative savings overtake your net cost — to the year.
Break-even →Solar Payback Period Tool
A fast, simplified payback estimate with one-click state presets built in.
Quick →Which solar calculator should I use?
If you only have time for one tool, use the Solar Payback Calculator. It answers the question almost every homeowner asks first: how many years until this pays for itself? From there, the right tool depends on your decision:
- Paying cash? Run the ROI Calculator and Break-Even Calculator to see your lifetime return.
- Borrowing? The Loan Calculator shows your monthly payment and whether savings cover it from month one.
- Offered a lease or PPA? The Lease vs Buy Calculator reveals the long-term cost difference most sales reps gloss over.
- Not sure what's cheapest? The Financing Calculator stacks all four payment methods side by side.
- Installed in 2025? The Tax Credit Calculator checks whether your system qualifies for the 30% credit on your 2025 return. Systems installed in 2026 do not.
Once you know roughly how solar pays off, check the deal in your own state — incentives and electricity rates change the math more than anything else.