Free calculators for U.S. homeowners.

Run the numbers on solar, heat pumps, and your energy bill.

Use free calculators to model solar payback, bill savings, and heat pump economics with editable assumptions for U.S. homeowners.

Isometric house illustration with solar panels and heat pump

Start with the free solar payback calculator

To use the free solar payback calculator, you'll need:

ZIP code
Average monthly electric bill

Optional

Annual or monthly electricity usage
Confirmed incentives
Battery backup

Zip codeAverage monthly electric bill

Use utility usage for better sizing accuracyAdd the usage from your utility account if you know it. Your bill still drives the savings side of the estimate.

Include Home Battery BackupStore daytime solar power for nights and blackouts. Highly recommended for states with Net Metering 3.0.

Include confirmed incentives?Enter only incentives you have confirmed, such as a state rebate, utility rebate, installer discount, or tax credit that applies to your install date.

Customize advanced assumptions

How this works

Enter your monthly bill or utility usage and we will estimate system size, installation cost, and first-year savings automatically. Zip code is optional and only localizes the rate and production assumptions.

Live resultsZIP optional

Ready for your estimate

Enter your monthly bill or utility usage to generate live results.

Start with your average monthly bill or utility-usage data. Add your zip code any time to replace the fallback electricity-rate assumption with localized data.

Planning note

Enter your monthly bill or utility usage first. Zip code stays optional and only localizes the estimate.

Before you compare quotes

Use the homepage estimate as a planning baseline

The calculator uses your ZIP code, monthly bill, optional utility usage, and only the incentives you confirm. Treat the result as a fast first pass before you compare it with roof-specific layouts, local tariffs, financing terms, or contractor pricing.

No phone number requiredEditable assumptionsPlanning estimate only

Review assumptions and sources

What the estimate uses

ZIP code and average monthly electric bill
Optional utility usage for better sizing accuracy
Confirmed incentives you enter yourself
Editable inputs before you compare a quote

What it cannot know yet

Roof shape, shading, and exact panel layout
Financing terms, dealer fees, and contractor pricing
Utility tariff details, permitting, or interconnection rules
Property-specific production until you confirm one roof on a map

Flagship Solar Report

Want roof-specific solar results?

Open Flagship Calculator

Confirm one property, check Google Solar data availability, and unlock a private report for one address.

Google Solar availability is checked before payment. Private 7-day report link.

For one confirmed property, it adds:

Starts with the same planning baseline as the free calculator
confirm one roof on a map
check Google Solar data availability
get a private solar scenario for one property
review roof-specific sizing and output estimates
use one property-specific scenario for quote comparison