Compare costs, payback, and tradeoffs using assumptions you can change.
Curated tools for common financial crossroads.
Calculate total monthly mortgage payments including property taxes, homeowners insurance, and PMI, plus interest saved from extra principal payments.
Compare the total multi-year cost of buying a home against renting and investing the difference, including maintenance, taxes, and equity.
Compare home heating costs between an electric heat pump and heating oil, propane, or natural gas, including seasonal efficiency and break-even fuel prices.
Calculate monthly auto loan payments, total interest paid, dealer fees, and sales tax savings from a vehicle trade-in.
Calculate rooftop solar panel production, electricity bill savings, payback timeline, and net lifetime return using local NREL weather data.
Try searching for loan, solar, heat pump, or car. Or browse all categories below.
Transparent assumptions, month-by-month cash flows, and no sponsored results.
Solar, heating, batteries, insulation, and household energy costs.
Calculate rooftop solar panel production, electricity bill savings, payback timeline, and net lifetime return using local NREL weather data.
Compare home heating costs between an electric heat pump and heating oil, propane, or natural gas, including seasonal efficiency and break-even fuel prices.
Evaluate home battery economics across time-of-use rate shifting, solar self-consumption, and the required value of emergency backup power.
Calculate the hourly, monthly, and annual electricity cost to run household appliances at your electric rate, and compare efficient replacement options.
Compare electric and gas water heater operating costs against a hybrid heat pump water heater to calculate annual savings and payback.
Calculate heating and cooling bill savings from upgrading attic insulation and sealing air leaks, factoring in utility rebates to find payback.
Compare appliance repair quotes against replacement prices, delivery fees, energy efficiency savings, and remaining service life equity to find your break-even repair ceiling.
Mortgages, car loans, personal loans, refinancing, and payoff strategies.
Calculate total monthly mortgage payments including property taxes, homeowners insurance, and PMI, plus interest saved from extra principal payments.
Calculate when mortgage refinance payment savings recoup closing costs, and compare principal reduction and net lifetime cost.
Compare upfront mortgage discount point costs against monthly payment savings to calculate your estimated break-even timeline.
Calculate monthly auto loan payments, total interest paid, dealer fees, and sales tax savings from a vehicle trade-in.
Compare personal loan offers by calculating estimated APR with origination fees, monthly payments, and total financing costs.
Compare a low-rate dealer financing incentive against a cash rebate with outside bank financing to find the lower total cost.
Compare existing debt payments with a new consolidation loan or balance transfer offer to calculate interest saved and payoff time.
Compare debt snowball, avalanche, and minimum payment strategies to calculate your estimated payoff date and total interest paid.
Calculate how long it takes to pay off credit card balances under minimum payments, fixed monthly amounts, or a target payoff date.
Electric, hybrid, and gas vehicles.
Compare electric vehicle and gas car ownership costs, including per-mile energy, home charging setup, maintenance, and loan payments.
Compare fuel consumption, gas costs, and upfront price differences between hybrid and conventional gas vehicles to calculate payback.
Compare the cost of fixing your current vehicle against purchasing a replacement car to find your break-even repair threshold and total costs.
Compare monthly lease payments, acquisition fees, and mileage penalties against loan payments, depreciation, ending vehicle equity, and break-even resale value.
Renting versus buying, major purchases, and cash tradeoffs.
Compare paying down a mortgage early against investing extra cash in a portfolio, evaluating break-even investment returns and ending wealth.
Compare financing home improvements with a HELOC against paying cash, evaluating interest paid, cash opportunity cost, and liquidity.
Compare the total multi-year cost of buying a home against renting and investing the difference, including maintenance, taxes, and equity.
Compare upfront annual subscription costs with monthly payments to find your break-even usage months, discounts, and net savings.
Compare annual membership fees against grocery and retail savings, gas discounts, and extra travel costs to find your break-even spending.
Compare cash checkout discounts against credit card rewards, interest-free float, and financing APR to decide whether paying cash or card pays.
Compare annual fee credit cards against a no-fee cash back baseline, calculating break-even spending thresholds and the net value of usable perks.
Duplex utilities, small landlords, and business decisions.
Calculate fair utility bill splits between duplex units by square footage, occupancy, or equal share, and evaluate submeter payback.
Compare upfront setup costs and monthly software subscriptions against usable labor hours saved to calculate payback and net ROI.
Compare gross salary raises against marginal tax drag, vehicle mileage, transit fares, and lost travel time to calculate your true net take-home and effective hourly wage.
Compare equipment rental rates against purchase prices, sales tax, annual maintenance, storage costs, and residual resale equity to find your break-even days.
Most online calculators exist to capture your lead and sell you a loan, a panel, or a contractor quote. Does It Pay? is built differently:
Every rate, price, and assumption is visible and editable. Default numbers cite their primary sources with the exact date checked.
We compute month-by-month cash flows and include flat-price sensitivity tests, so you know what happens if energy prices do not rise.
All calculations run directly inside your browser. No account, no email address, no tracker, and no server database.
Trust and methodology: All math models and formulas are documented, open, and test-verified offline.
We are researching and building practical decision calculators across personal finance, home ownership, and work. Upcoming tools in research include: