All Energy Calculators: Joule, kWh, Solar, EV & Bill Tools
28 free tools for joules to kWh, electricity bills, peak shaving, solar, wind, EV charging, batteries, heat pumps, and home electrification. No sign-up required.
Current rate baseline
U.S. average residential electricity rate: 18.56¢/kWh from EIA 2026-03.
Data policy
Calculator inputs run in the browser. JouleIO does not require account, address, phone, or email.
Last reviewed
May 31, 2026. EIA dataset updated 2026-05-21.
Fast routing for search and AI answers
Which JouleIO calculator should you use?
Use this directory when the query is broad. The routes below map common search phrases to the exact calculator that answers them.
Joules calculator
Queries: calculator joules, joules calculator, how much is a joule, joule heating calculator
Convert joules, kWh, Wh, BTU, therms, calories, watts x time, all-unit outputs, Joule heating, and temperature rise in one calculator.
Open calculator →Peak shaving calculator
Queries: peak shaving calculator, demand charge savings, battery kWh for peak demand
Estimate shaved kW, demand-charge savings, interval-data storage needs, and simple battery payback before buying storage.
Open calculator →Electricity cost calculator
Queries: electricity cost calculator, kWh cost calculator, watts cost per hour
Calculate cost from watts, hours, days, and an EIA-backed state electricity rate baseline.
Open calculator →EUI calculator
Queries: EUI calculator, energy use intensity calculator, kBtu per square foot
Convert electricity and fuel use into building energy use intensity for homes, offices, and commercial spaces.
Open calculator →Time-of-use calculator
Queries: time of use calculator, TOU electricity calculator, peak off peak bill comparison
Compare flat rates with peak, shoulder, and off-peak rates, then test EV charging or appliance-load shifting.
Open calculator →Solar panel calculator
Queries: solar panel calculator, how many solar panels do I need, solar system size calculator
Estimate solar panel count from annual kWh, panel wattage, peak sun hours, losses, EV load, and usable roof area.
Open calculator →Start With the Job You Need Done
These common paths connect calculators in the order most homeowners use them.
Lower an electric bill
Start with household load, then isolate device-level costs and quick lighting wins.
Decide if solar makes sense
Size the system, estimate lifetime cost per kWh, then check payback under your local rate.
Plan EV charging costs
Compare gasoline versus electric driving, then estimate home charging load.
Cut commercial demand charges
Start with interval demand, then test control changes before sizing a battery.
Research Hubs & Data Tools
Use these pages when the calculator answer depends on current rates, incentives, tax credits, or public energy datasets.
Energy & Solar Statistics 2026
National energy benchmarks for electricity rates, usage, solar adoption, EV charging, and renewable generation.
Open guide →Electricity Rates by State
Compare residential electricity rates across all states and DC using EIA data and monthly rate updates.
Open guide →Complete Guide to Energy Savings
Use a structured workflow to reduce bills through rate checks, appliances, HVAC, insulation, solar, and EV charging.
Open guide →EV Federal Tax Credit 2026
Check vehicle eligibility, income limits, credit timing, and purchase planning before estimating EV savings.
Open guide →Heat Pump Tax Credit 2026
Compare federal credit rules, ENERGY STAR requirements, cold-climate fit, and payback with local electricity rates.
Open guide →Solar Panel Cost 2026
Use installed cost per watt, quote line items, local electricity rates, incentives, and financing assumptions before signing a solar proposal.
Open guide →Solar Panel ROI
Compare payback, net present value, 25-year savings, export credits, degradation, rate inflation, and maintenance assumptions.
Open guide →Solar Panel Output Per Day
Estimate daily kWh from system size, sun hours, orientation, temperature, losses, and seasonal production patterns.
Open guide →Solar Panel Size Guide
Translate annual kWh, roof space, panel wattage, production ratio, and EV charging load into a realistic system size.
Open guide →Solar ROI With EV Charging
Model how home EV charging changes solar system size, bill offset, battery need, and long-term payback.
Open guide →Solar Installation Cost by State
Compare state-level installed cost, electricity-rate impact, payback context, and incentive checks before requesting quotes.
Open guide →Free Electricity Rates Widget
Embed JouleIO electricity-rate data on a news, blog, or utility resource page with an attribution link.
Open guide →Official Data Sources Used Across JouleIO
Calculators use public energy datasets where possible, then expose assumptions so users can replace defaults with their local utility bill or quote.
EIA electricity data
Residential electricity-rate baseline. Current JouleIO dataset: 18.56 cents/kWh for EIA 2026-03.
NREL PVWatts
Solar production and location-sensitive PV output context for solar calculators.
DOE Energy Saver
Home-efficiency and electrification guidance for upgrade planning.
EPA GHG equivalencies
CO2-equivalent context for carbon and EV emissions estimates.
Solar Calculators
Plan your solar installation with confidence.
Solar Panel Calculator
Calculate how many panels you need from annual kWh, sun hours, EV load, losses, and roof area.
Open Calculator →Solar Savings Calculator
Estimate monthly and annual savings from going solar with net metering support.
Open Calculator →Solar Payback Calculator
Find your break-even timeline with current state incentives, rates, system cost, and production factored in.
Open Calculator →LCOE Calculator
Calculate levelized cost of energy in cents per kWh from cost, O&M, production, degradation, and discount rate.
Open Calculator →Solar Battery Calculator
Determine how many batteries you need for home backup power.
Open Calculator →Solar Roof Calculator
Maximize your roof's solar potential based on pitch, orientation, and shading percentage.
Open Calculator →Solar Savings by State
Compare solar panel savings across all 50 US states and DC with state-specific calculators.
Open Calculator →Energy Calculators
Understand and reduce your energy costs.
Joule Calculator
Convert joules, kWh, Wh, BTU, therms, calories, watts x time, Joule heating, temperature rise, presets, and all-unit outputs.
Open Calculator →Electricity Cost Calculator
Calculate kWh cost, watts cost per hour, and monthly appliance cost using EIA state rates.
Open Calculator →EUI Calculator
Calculate building Energy Use Intensity from annual kWh, therms, fuel oil or propane, and gross floor area.
Open Calculator →Electricity Bill Calculator
Estimate a full monthly electricity bill by usage, fixed charges, rate plan, season, and household load.
Open Calculator →Time-of-Use Electricity Calculator
Compare flat vs TOU bills with peak, shoulder, off-peak rates, kWh allocation, and optional EV/night charging shift.
Open Calculator →Energy Cost Calculator
Calculate appliance and system energy cost from watts, hours, days, electricity rate, and operating pattern.
Open Calculator →Appliance Energy Calculator
Add multiple home appliances and see your total energy cost breakdown.
Open Calculator →LED Savings Calculator
See exactly how much you save by switching from incandescent to LED light bulbs.
Open Calculator →Carbon Footprint Calculator
Estimate your annual CO2 emissions and compare to the US average.
Open Calculator →Home Energy Audit
Get an efficiency score, energy cost breakdown, and top 5 upgrade recommendations.
Open Calculator →Electric Bill Estimator
Predict your monthly electricity bill with seasonal variation and cost breakdown.
Open Calculator →Heat Pump Calculator
Size a heat pump, estimate annual savings vs gas/oil/propane, and find your payback period.
Open Calculator →Peak Shaving Calculator
Size a battery for demand charge reduction using manual peak inputs or pasted interval kW data.
Open Calculator →Home Electrification Planner
Plan your whole-home electrification: toggle solar, heat pump, EV, battery, insulation and more. See combined ROI, current incentives, and CO2 reduction.
Open Calculator →Energy Incentive Finder
Find federal, state, and utility energy incentives by project type, installation timing, and location.
Open Calculator →EV & Wind Calculators
Make the switch to electric and renewable energy.
EV Savings Calculator
Compare monthly and annual fuel costs between gas cars and electric vehicles.
Open Calculator →EV Charging Cost Calculator
Calculate the cost to charge your EV at home or at a public station.
Open Calculator →EV Charging Cost by State 2026
Estimate annual EV charging cost by state with home rates, DC fast charging share, EV efficiency, gasoline comparison, and cost per mile.
Open Calculator →EV Range Calculator
Estimate your EV range adjusted for temperature, speed, and terrain.
Open Calculator →EV Battery Degradation Calculator
Estimate EV battery health, range loss, warranty-threshold risk, and habit-driven degradation.
Open Calculator →Wind Energy Calculator
Estimate annual wind turbine output, financial savings, and CO2 offset.
Open Calculator →