See how many solar panels fit on your roof
Type your address. We measure your roof from satellite data, lay out every panel, and show what it would produce, cost and save.
- No account and no sales calls
- Real roof measurements for your home
- Equipment list and savings report included
Get your free roof estimate
Enter your home address to start.
Your solar plan in three steps
The same roof measurements installers use to start a design, without waiting for a call back.
Enter your address
We find your building and measure every roof face: size, pitch, direction and how much sun it gets.
Pick your system size
Drag the slider or type a panel count. Panels fill the sunniest spots first, and every number updates live.
Get your report
See the equipment you’d need, then unlock your bill before and after solar, payback and 25-year savings.
What’s in your solar plan
Click through the tools you get for your address.
Every panel on your actual roof
Panels are drawn on satellite imagery of your home and colored by how much sun each spot gets.
- 400 W panels placed where they fit
- Sunniest spots fill first
- Drag a slider to add or remove panels
Each roof face measured
See the direction, pitch, size and yearly sun hours of every face of your roof, and how many panels go on each.
- Compass direction and pitch (like 6/12)
- Roof area in square feet
- Panels and kWh per face
How much sun each panel gets
Google’s shading analysis ranks every panel spot by how much energy it makes in a year, accounting for trees and nearby buildings.
- Yearly kWh for every panel spot
- Best and weakest spots on your roof
- Peak sun hours per year
Compare every system size
A chart of every layout that fits your roof against how much electricity your home uses, so you can see the right size at a glance.
- Production for each panel count
- Your yearly use marked on the chart
- One click to match your usage
A complete parts list
The estimator sizes a hybrid system that keeps working in an outage: inverters, whole-home backup switching and batteries.
- EG4 FlexBOSS21 hybrid inverters
- GridBOSS whole-home backup
- Batteries for about 12 hours of use
25 years of savings
Your monthly bill before and after solar, installed cost, payback year and lifetime savings at your local electricity price.
- Bill before and after solar
- Payback year and 25-year total
- Tons of CO₂ avoided
How big a solar system do I need?
A quick estimate from your electric bill. The estimator then checks it against your real roof.
Uses your state’s average price (EIA 2024) and a typical 1,350 kWh per kW of panels per year. Installed cost at $3/W before incentives. Your roof’s direction and shade change the real numbers.
Real quotes, only if you ask
Your plan is yours to keep. If you want real prices, send it to up to three local installers who can confirm the design with a site visit.
- No calls unless you request quotes
- Installers see your roof plan, so quotes start faster
- Opt out of data sharing any time
What does electricity cost where you live?
Solar pays back fastest where power is expensive. The average US home pays 16.5¢ per kWh; Texas homes pay 14.9¢ and use 1,096 kWh a month (EIA, 2024).
| State | ¢/kWh | Avg bill | |
|---|---|---|---|
| Hawaii | 42.9 | $212 | |
| California | 32.0 | $161 | |
| Massachusetts | 29.4 | $167 | |
| Connecticut | 28.8 | $200 | |
| Rhode Island | 28.6 | $162 | |
| North Dakota | 11.5 | $118 | |
| Idaho | 11.5 | $109 | |
| Nebraska | 11.5 | $110 | |
| Louisiana | 11.7 | $141 | |
| Washington | 11.9 | $114 |
Frequently asked questions
Is the Solar Roof Estimator really free?
Yes. There is no account and no sales call. You see your roof layout, yearly production and the equipment it needs right away. The full savings and payback report is free too; enter your email to unlock it on this page.
How does it know what my roof looks like?
It uses Google’s Solar API, which measures each face of your roof (size, pitch, direction and shade) from satellite and aerial imagery, then lays out panels where they fit and get the most sun.
How accurate is the estimate?
It is a planning estimate, not a quote. Imagery can be a few years old, and trees, vents and local code can change what fits. An installer confirms everything with a site visit.
What size system do I need?
It depends on how much electricity you use. The average US home uses about 863 kWh a month. The estimator starts you at the system that covers an average home in your state, and you can adjust it to your own bill.
What inverter and batteries would I need?
The estimator sizes an EG4 hybrid system: FlexBOSS21 inverters for the panels, a GridBOSS for whole-home backup switching, and wall-mount batteries for about half a day of average use.
Do you sell my information?
If you ask for quotes, we send your request to up to three solar installers. We may also share the addresses people look up, their results, and contact details they give us with solar partners, as our Privacy Policy explains. You can opt out at any time, and we honor Global Privacy Control signals.
Ready to see your roof?
It takes about ten seconds.