Does solar pay off?
Free solar calculators. Size your system, estimate the cost after the 30% federal tax credit, and see exactly how many years until it pays off and what you pocket after that.
Estimate your solar system cost
Solar Cost & Savings Tools
Run your own numbers before you sit down with an installer.
Solar Panel Cost Calculator
Enter system size and cost per watt to see gross cost, your 30% credit, and what you actually pay.
Check the range →Solar Savings Calculator
Enter your net cost and monthly bill to see payback period and 25-year savings total.
Check the range →Solar System Size Calculator
Enter monthly kWh and local sun hours to get system size and approximate panel count.
Check the range →Solar Tax Credit Calculator
Enter system cost and battery cost to see your federal credit and net cost after it applies.
Check the range →Solar is a 25-year investment. Model it first.
Installers know monthly-payment math cold. They are less forthcoming about payback period, which is the number that actually tells you whether solar makes financial sense. These tools size a system from your actual usage, apply the 30% federal credit, and show how long until solar covers its own cost and what you keep after that.
Which tool to open first
The four calculators answer different questions, and most people only need one or two of them.
- Getting your first installer quotes and want to know if the number is fair: start with the Solar Panel Cost Calculator. Enter the size they proposed and their price per watt, and you get the same net figure they should be showing you after the credit.
- Already have a cost number and want to know if it is worth it: use the Solar Savings Calculator. It turns your net cost and current bill into a payback period, which is the number that actually answers the "worth it" question.
- Haven't talked to an installer yet and want a ballpark before you do: run the Solar System Size Calculator first. It estimates the kW you need from your usage, which you can then feed into the cost calculator.
- Adding a battery or trying to separate the credit from the rest of the math: the Solar Tax Credit Calculator isolates just the 30% credit calculation, including battery storage.
A full example, start to finish
Take an 8 kW system, priced at $3.00 per watt, which is the default in the calculators above and a reasonable middle-of-the-road 2025 to 2026 quote.
- Gross cost: 8,000 watts × $3.00 = $24,000
- Federal credit at 30%: $24,000 × 0.30 = $7,200
- Net cost after the credit: $24,000 minus $7,200 = $16,800
Now run that $16,800 net cost through the savings calculator with a $180 monthly bill, 90% of the bill offset, and a 3% annual utility rate increase. Year one savings come to $1,944. Divide the net cost by that and payback lands at about 8.6 years. Compound the savings forward through year 25 at the same 3% rate and the running total reaches roughly $70,877, or about $54,077 ahead of what the system cost after the credit. Change any of the four inputs, size, price per watt, monthly bill, or rate increase, and every downstream number in that chain moves with it.
What these calculators assume, and what they do not know
Every number here comes from the inputs you type in, run through the arithmetic shown above. Nothing is pulled from a database of local pricing or your actual utility rate. The 30% figure is the federal Residential Clean Energy Credit rate as published by the IRS, applied to whatever cost you enter. The savings calculator assumes your utility rate rises at a constant percentage every year, which is a simplification. Real rate changes happen in irregular steps set by state regulators, not smooth annual increases. The system size calculator's 0.8 efficiency factor is a standard industry planning assumption for inverter and wiring losses, not a measurement of any specific roof. None of these tools account for roof shading, panel degradation, financing terms, or local permitting costs, all of which an installer's site visit will surface. Treat every result as a planning number to bring into that conversation, not a substitute for it.
Where these numbers come from
The federal credit rate, the payback math, and the sizing formula on this site all trace back to these primary sources:
- DOE Homeowner Solar Guide (federal guide to going solar)
- IRS Clean Energy Credit (the 30% federal solar tax credit)
- ENERGY STAR (efficiency and rebate programs)
Before you decide: common questions
How much is a solar system for a 2000 sq ft house?
A 2,000 square foot home typically needs a 6 to 10 kilowatt system, costing roughly $18,000 to $30,000 before incentives. The 30% federal tax credit (available through 2032 per the IRS) brings the net cost to $12,600 to $21,000. State rebates and local utility programs can trim it further. Prices vary by installer, panel brand, and roof complexity. Get at least three quotes before deciding.
How much does a normal solar panel cost?
A single residential panel typically costs $250 to $400, depending on wattage and brand. Most homes need 15 to 25 of them. The number that matters more is total installed cost per watt, which covers inverters, mounting hardware, wiring, permits, and labor. In 2025 and 2026, that average runs about $2.50 to $3.50 per watt before incentives. Energy.gov and EnergySage both carry regional cost data.
Why is my electric bill so high if I have solar panels?
A few things can keep bills high despite having panels installed. The system may be undersized for your actual usage, or consumption may have grown from added loads like an EV or new HVAC. Shading, cloudy periods, and aging equipment all reduce output too. If you are on net metering, billing structure changes at your utility can affect what you get credited. Check your system monitoring app to compare expected and actual production, then call your installer if output is running below estimates.
Are solar panels worth money?
For most US homeowners, yes. Average payback runs 6 to 12 years, after which electricity savings are essentially free money. The 30% federal tax credit improves those returns substantially. Home resale value also tends to go up with owned solar. The variables that matter most are your local utility rate, sun exposure, and roof condition. Loans and leases produce different financial outcomes than a cash purchase, often quite different. Get a site-specific analysis from a certified installer before committing.
These calculators get you close enough to know whether a quote is worth pursuing. The last mile, roof condition, shading, permitting timelines, and your specific utility's net metering rules, only a licensed installer who has actually seen your property can price. Bring your numbers from here into that conversation instead of starting it cold.