FREE SOLAR CALCULATORS
Know Exactly What Solar Will Save You
Run the numbers before you commit. Every solar calculator you need — savings, payback, batteries, tax credits, financing, and more. Free, instant, no sales calls.
AVERAGE 25-YEAR SAVINGS
$42,300
SolarToolsOnline est. — 8.5kW system, 3%/yr rate escalation, 25-yr lifetime
PAYBACK PERIOD
9–12 yrs
NREL/industry avg — residential, no ITC or state rebates
COMMERCIAL ITC
30%
Section 48E — construction must begin by July 4, 2026
SHOWING 40 CALCULATORS
Free Solar Calculators
Federal Solar Tax Credit Calculator
Calculate your federal solar tax credit (applies to systems installed by Dec 31, 2025).
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Solar Battery Size Calculator
Find the right battery storage capacity for your home energy needs.
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Solar Energy Production Calculator
Estimate daily, monthly, and annual kWh output from your solar array.
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Solar Lease vs Buy Calculator
Compare total costs of leasing versus purchasing your solar system.
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Solar Loan Calculator
Calculate monthly loan payments and total interest for solar financing.
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Solar Panel Count Calculator
Determine how many solar panels you need to meet your energy goals.
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Solar Panel Savings Calculator
Estimate total savings over the lifetime of your solar system.
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Solar Payback Period Calculator
Find out exactly how many years until your system pays for itself.
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Solar ROI Calculator
Calculate your return on investment and annual yield percentage.
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Solar System Size Calculator
Size your solar system correctly based on usage and production goals.
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Battery Backup Duration Calculator
See how long your battery will power your home during an outage.
Commercial Solar ROI Calculator
ROI analysis for commercial and industrial solar installations.
Community Solar Savings Calculator
Calculate bill credits and savings from community solar subscriptions.
Electricity Escalation Calculator
Project future utility costs with annual rate escalation modeling.
Electricity Offset Calculator
Find what percentage of your electric bill solar will offset.
EV Solar Charging Calculator
Calculate solar panels needed to charge your electric vehicle for free.
Grid vs Off-Grid Solar Calculator
Compare costs and benefits of grid-tied versus off-grid systems.
Home Energy Usage Calculator
Estimate your total home energy consumption for solar sizing.
Lifetime Solar Value Calculator
Calculate the full 25-year net present value of going solar.
Net Metering Calculator
Calculate credits earned from excess solar energy sent to the grid.
Roof Solar Capacity Calculator
Find the maximum solar capacity your roof can physically support.
Solar Break-Even Calculator
Find the exact month and year your solar investment breaks even.
Solar Carbon Offset Calculator
Measure your environmental impact and carbon footprint reduction.
Solar Degradation Calculator
Model panel performance loss over time using degradation rates.
Solar Depreciation Calculator
Calculate MACRS and bonus depreciation for business solar systems.
Solar Energy Independence Calculator
Find out what percentage of your energy can come from solar alone.
Solar Financing Comparison Calculator
Compare cash, loan, lease, and PPA side-by-side over 25 years.
Solar Installation Cost Calculator
Get a detailed cost estimate based on system size and location.
Solar Insurance Calculator
Estimate added homeowners insurance costs for solar panel systems.
Solar Inverter Size Calculator
Determine the right inverter capacity for your solar array.
Solar Lease Buyout Calculator
Decide if buying out your solar lease is financially worthwhile.
Solar Panel Efficiency Calculator
Compare panel efficiency ratings and their impact on energy output.
Solar PPA Calculator
Evaluate power purchase agreements and compare to buying outright.
Solar Rebate vs Tax Credit Calculator
Compare the net value of upfront rebates versus tax credits.
Solar String Sizing Calculator
Design panel string configurations for your inverter specifications.
Solar Tilt Angle Calculator
Find the optimal panel tilt angle for maximum energy production.
Solar vs Utility Cost Calculator
Compare the true lifetime cost of solar versus staying on the grid.
Solar Water Heater Savings Calculator
Estimate savings from switching to solar hot water heating.
SREC Value Calculator
Estimate annual income from Solar Renewable Energy Certificates.
State Solar Rebate Calculator
Look up state-level rebates and incentives available in your area.
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