Free Solar Calculators
448+ calculators for panels, batteries, inverters, wiring, and ROI. Instant results, no signup.
Residential Solar
Size your home solar system — panels, production, and roof fit.
☀ Solar Panel Calculator
How many panels does your home need? Enter your bill, get your answer.
🏠 How Many Solar Panels Do I Need
The #1 question. Your electricity bill in — panel count out.
⚡ Solar System Size Calculator
Calculate the right kW system size for your home.
🌞 Peak Sun Hours Calculator
Find peak sun hours for your location. The key to accurate sizing.
📐 Solar Panel Tilt Calculator
Optimal tilt angle for maximum energy production year-round.
🔌 Solar Power Calculator
How much power will your solar array actually produce?
📊 Solar Panel Comparison
Compare two panels side-by-side: 25-year production, cost per kWh, and value winner.
🏛 Ground Mount Solar Calculator
Calculate land area, row spacing, and cost for ground-mounted solar arrays.
🏗 Solar Roof Load Calculator
Check if your roof can support the weight of solar panels and snow.
📐 Row Spacing Calculator
Calculate minimum panel row spacing to prevent inter-row shading.
🌡 Temperature Coefficient Calculator
See how heat reduces your panel output month by month.
🏠 Solar Pergola Calculator
Size a solar pergola: panels that fit, power output, and shade area.
❄ Snow Load & Winter Calculator
Assess snow weight on panels and estimate winter production losses.
📈 Panel Degradation Calculator
Project your panel output decline over 25 years.
☀ Bifacial Panel Calculator
Calculate rear-side energy gain from bifacial solar panels.
❄ Solar Mini Split Calculator
Size solar panels to power a ductless mini split heat pump.
💧 Solar Tankless Water Heater
Calculate solar offset for electric tankless water heaters.
🔌 Solar Dryer Calculator
How many panels to offset your clothes dryer's energy use.
🌡 Solar Space Heater Calculator
Solar offset for electric heaters with heat pump comparison.
🏠 Solar ADU Calculator
Size solar for accessory dwelling units with Title 24 compliance.
🐟 Solar Aquarium Calculator
Power your fish tank equipment with solar panels.
💧 Solar Dehumidifier Calculator
Solar offset for whole-house or basement dehumidifiers.
🔌 Solar Washing Machine Calculator
Solar panels for washing machine with water heating analysis.
🌍 Solar + Geothermal Calculator
Combined net-zero HVAC system with solar and geothermal.
💨 Solar ERV Calculator
Energy recovery ventilation powered by solar panels.
❄ Solar Portable AC Calculator
Size solar for portable air conditioners.
☀ Solar Shingle vs Panel Calculator
Side-by-side cost and ROI comparison.
💧 Solar Thermosiphon Calculator
Passive solar water heating system sizing.
☀ Perovskite Solar Calculator
2026 tandem panel efficiency comparison vs silicon.
💧 Solar Sauna Calculator
Traditional and infrared sauna solar sizing.
🌡 Solar Radiant Floor Heating
BTU sizing for solar-powered heated floors.
🍷 Solar Wine Cellar Calculator
Constant 55°F cooling with solar panels.
📊 LG vs Panasonic vs REC
Premium panel 3-way comparison (includes LG discontinuation warning).
📊 Trina vs JA Solar vs LONGi
3-way Tier 1 panel comparison.
🌡 Solar + HVAC Combo
Bundled tax credit ROI for solar and HVAC systems.
☀ Aiko ABC Panels Calculator
All-Back-Contact premium aesthetic panel sizing.
Battery & Storage
Size your battery bank for backup, off-grid, or self-consumption.
🔋 Solar Battery Calculator
What battery size do you need? Based on your loads and backup hours.
⚡ Battery Bank Size Calculator
Calculate amp-hours and watt-hours for your battery bank.
🔧 Battery Sizing Calculator
Lead-acid vs lithium — the right capacity for your system.
🌐 Tesla Powerwall Calculator
How many Powerwalls for your home? Based on daily usage.
⏱ Battery Runtime Calculator
How long will your battery last under load?
⏻ Battery Charge Time Calculator
How long to charge your battery bank from solar?
🚘 V2H Calculator
Use your EV battery to power your home with vehicle-to-home technology.
🔋 Sodium-Ion vs LFP
Compare sodium-ion, LFP, and lead-acid batteries for solar storage.
🕐 TOU Battery Optimizer
Optimize battery charge/discharge schedule for time-of-use rates.
📊 Battery Chemistry Comparison
Compare LFP, NMC, LTO, Na-ion, and lead-acid side-by-side.
🔋 Jackery vs EcoFlow vs Goal Zero
3-way portable power station comparison.
📊 EcoFlow Delta Pro vs Powerwall
Portable vs fixed home backup comparison.
📈 Battery vs Generator 10-yr TCO
Full total cost of ownership comparison.
📊 BYD vs Tesla Powerwall
$/kWh comparison with inverter bundling.
📊 Generac PWRcell vs Powerwall
With ATS and generator ecosystem comparison.
🔋 Pylontech Battery Calculator
Modular LiFePO4 best value battery sizing.
Inverters & Controllers
Size inverters and charge controllers for your solar system.
🔄 Solar Inverter Size Calculator
What inverter wattage for your loads? Don't forget surge.
⚙ Charge Controller Calculator
MPPT or PWM? Calculate the right amp rating.
🔌 Inverter Sizing Calculator
Match your inverter to your peak and continuous loads.
🔗 String Sizing Calculator
Panels in series vs parallel — voltage and current optimization.
🔄 Inverter Clipping Loss Calculator
Calculate energy lost from DC:AC ratio oversizing.
📊 Tesla vs SolarEdge vs Enphase
3-way inverter topology comparison.
🔄 Growatt vs Victron
Budget vs premium off-grid inverter comparison.
📊 Inverter Efficiency Curve
CEC vs Euro weighted efficiency.
📊 Fronius vs SMA
Premium European string inverters comparison.
📊 Sol-Ark vs EG4
Hybrid inverter + bypass switch cost comparison.
📊 Huawei vs Sungrow vs SMA
3-way comparison with US/UK ban logic.
🔸 Hoymiles Microinverter Calculator
Budget Enphase alternative microinverter sizing.
🔄 Sungrow Inverter Calculator
World #1 inverter manufacturer sizing guide.
🔄 Solis Inverter Calculator
Budget hybrid with Pylontech support sizing.
🔄 Deye Inverter Calculator
Off-grid + hybrid stackable to 192kW sizing.
Wiring & Electrical
Wire sizing, voltage drop, fuses, and electrical safety.
🔌 Solar Wire Size Calculator
AWG or mm² — pick the right wire gauge for your solar run.
⚡ Voltage Drop Calculator
Keep voltage loss under 3%. Calculate it before you wire.
🔸 Amps Calculator
Watts to amps, amps to watts. The conversion you always need.
Ω Ohm's Law Calculator
V = IR. Calculate voltage, current, resistance, and power.
🔧 Solar Conduit Fill Calculator
NEC-compliant PV conduit sizing for solar installations.
🔸 Rapid Shutdown Calculator
NEC 690.12 compliance checker for rapid shutdown requirements.
⚡ Solar Grounding Calculator
NEC 250/690 grounding requirements for solar PV systems.
🔸 NEC Fault Protection
GFDI, AFCI, rapid shutdown compliance.
Off-Grid Systems
Complete off-grid system sizing for cabins, tiny homes, and remote sites.
🏔 Off-Grid Solar Calculator
Complete system sizing: panels, batteries, inverter, controller.
🏡 Cabin Solar Calculator
Weekend cabin or full-time? Size your off-grid system.
🏠 Tiny House Solar Calculator
Tiny house, big energy needs. Get the math right.
🔋 Solar Generator Calculator
Portable power station sizing for camping and emergencies.
🔄 Solar vs Generator
Side-by-side 20-year cost comparison of solar vs fuel generators.
🚘 Solar Carport Calculator
Size a solar carport: panels, power, EV miles, and cost.
🏠 Garage & Workshop Solar
Power tools, EV charging, and lighting from solar.
🍱 Food Truck Solar Calculator
Replace your generator with rooftop solar panels.
🚰 Container Home Solar
Size solar for shipping container homes with heat analysis.
💧 Solar Irrigation Calculator
Size a solar water pump for agricultural irrigation.
🌿 Solar Greenhouse Calculator
Power grow lights, ventilation, and heating mats with solar.
🐓 Solar Chicken Coop
Automatic doors, heated waterers, and egg-production lighting.
❄ Solar Freezer Calculator
Size solar for chest or upright freezer with food safety planning.
⚡ Microgrid Sizing Calculator
Design a residential microgrid with islanding capability.
🔌 Solar CPAP Calculator
Size a portable solar system for CPAP therapy while camping.
💧 Solar Sump Pump Calculator
Solar-powered sump pump with emergency flood backup.
🌿 Solar Hydroponics Calculator
Power hydroponic grow systems with solar panels.
📷 Solar Security Camera Calculator
Size solar for remote security cameras without wiring.
⛽ Solar Campground/RV Park Calculator
Site-level solar sizing for campgrounds and RV parks.
❄ Solar Ice Maker Calculator
Off-grid ice production with solar panels.
📻 Solar Ham Radio Calculator
Portable and base station solar for amateur radio.
🏔 Solar Hunting Cabin Calculator
Seasonal off-grid cabin solar sizing.
🏠 Solar Garage Door Opener Calculator
Standalone solar for garage doors.
⛰ Solar Yurt Calculator
Off-grid power system sizing for yurt living.
⛵ Solar Houseboat Calculator
Liveaboard solar system sizing for houseboats.
🏕 Solar Glamping Calculator
Per-unit and site-wide solar sizing for glamping.
🏠 Solar Shepherd Hut Calculator
UK off-grid shepherd hut solar system in GBP.
🌿 Solar Aquaponics Calculator
Fish + plants combined system solar sizing.
🐟 Solar Fish Farm Calculator
Aeration and circulation for aquaculture solar sizing.
🏠 Solar Earthship Calculator
Passive + active solar for earthship homes.
🍄 Solar Mushroom Farm Calculator
Climate-controlled growing environment solar sizing.
🌩 Solar Disaster Relief Calculator
Deployable solar for emergency response.
🌳 Solar Treehouse Calculator
Lightweight solar with tree weight limits.
💧 Solar Irrigation Pivot Calculator
Center-pivot agricultural irrigation solar sizing.
🔥 Solar Wood Drying Kiln Calculator
Lumber dehumidification solar sizing.
🍱 Solar Food Dehydrator Calculator
Commercial drying solar sizing.
RV, Van & Boat
Mobile solar systems for RVs, campervans, and boats.
🚌 RV Solar Calculator
How much solar for your RV? Based on your actual appliances.
🚐 Van Life Solar Calculator
Van build solar sizing — roof space, loads, and battery.
⛵ Boat Solar Calculator
Marine solar system sizing with unique boat considerations.
❄ RV AC on Solar Calculator
Can you run air conditioning on solar? Let's do the math.
Financial & ROI
Solar costs, savings, payback period, and tax credits.
💰 Solar Panel Cost Calculator
Estimate total cost for your solar installation.
📈 Solar Savings Calculator
How much will solar save you over 25 years?
📊 Solar ROI Calculator
Return on investment — is solar worth it for you?
📅 Solar Payback Calculator
How many years until solar pays for itself?
⚡ Electricity Bill Calculator
What does your electricity actually cost per kWh?
🏷 Solar Tax Credit Calculator
Calculate your federal ITC solar tax credit.
🏠 Solar Home Value Calculator
Estimate how much solar panels increase your property value.
🔄 Self-Consumption Calculator
Optimize the ratio of solar energy used on-site vs exported.
📋 Solar PPA Calculator
Compare a Power Purchase Agreement to buying or staying on the grid.
💰 Community Solar Calculator
Calculate savings from community solar subscriptions for renters.
🔊 Panel Cleaning ROI
Is professional solar panel cleaning worth the cost?
📈 Battery Arbitrage Calculator
Calculate daily TOU arbitrage profit and payback for home batteries.
🏛 Solar Farm Calculator
Estimate income per acre for solar farm lease or self-development.
🏢 Commercial Solar Calculator
Size and calculate ROI for commercial rooftop solar with MACRS.
📊 MACRS Depreciation Calculator
Year-by-year solar depreciation schedule with 2026 bonus rates.
📋 Solar Financing Comparison
Compare cash vs loan vs lease vs PPA side-by-side over 25 years.
🚘 Solar Parking Lot Canopy
Size a solar canopy for commercial parking lots with EV charging.
📈 Rate Escalation Calculator
See how rising electricity rates multiply your solar savings over 25 years.
🔧 DIY vs Professional Solar
Compare costs, risks, and true savings of self-installation.
💰 Cost Breakdown Calculator
See where every dollar goes in a solar installation.
📋 Quote Comparison Tool
Compare 2-3 installer quotes normalized per watt and kWh.
⚡ VPP Earnings Calculator
Estimate virtual power plant income from your battery.
📈 Maintenance Cost Calculator
Plan your 25-year solar maintenance budget.
🍱 Solar Restaurant Calculator
Commercial solar ROI for restaurants with MACRS depreciation.
🏫 Solar for Schools Calculator
Public school solar with IRA direct pay — size system and calculate savings.
🚗 Solar Car Wash Calculator
Commercial solar ROI for car wash operations with MACRS.
🍇 Solar Vineyard/Winery Calculator
Agricultural solar with USDA REAP for vineyards and wineries.
🍺 Solar Brewery Calculator
Energy-intensive craft brewery solar ROI and payback.
⚡ Demand Charge Calculator
Peak shaving with solar + battery to reduce demand charges.
🔄 Grid Export Optimizer
Maximize self-consumption vs export for optimal solar earnings.
🔌 Solar Laundromat Calculator
Dryer-dominated energy with MACRS depreciation.
🔥 Solar Bakery Calculator
Commercial oven solar offset and ROI.
🐱 Solar Pet Grooming Calculator
High-velocity dryer solar sizing for pet groomers.
💰 Community Solar Subscriber
Bill credit calculator for renters subscribing to community solar.
📋 Solar Panel Insurance Calculator
Hail and hurricane risk assessment and premium estimator.
👜 Solar Daycare Center Calculator
Childcare facility solar with direct pay ITC.
🐹 Solar Veterinary Clinic Calculator
Clinic solar with critical backup sizing.
🚗 Solar Auto Repair Shop Calculator
High-demand shop solar with MACRS depreciation.
💰 Installer Commission Calculator
For solar sales reps.
📋 Loan APR Unmask
Expose hidden dealer fees in "low APR" loans.
📈 Solar Refinancing Calculator
Existing loan → HELOC refi analysis.
📋 Solar Lien & Home Sale
UCC-1 and payoff analysis for solar liens.
💰 VNEM Share Calculator
Community solar share allocation calculator.
📊 Monitoring Subscription Cost
Hidden fees by inverter brand.
📋 Permit Cost by Jurisdiction
AHJ permit fees calculator.
🚘 Solar EV Charger Station Calculator
Commercial EV station solar ROI for site hosts.
📺 Solar Billboard Calculator
Static and digital billboard solar sizing.
Energy Consumption
Understand your energy usage before sizing your solar system.
🎁 Appliance Energy Calculator
How much energy does each appliance use? Add them up.
⚡ kWh Calculator
Convert watts and hours to kilowatt-hours.
🔌 Power Consumption Calculator
Total power draw of your home or system.
🚘 EV Charging Calculator
How much solar to charge your electric vehicle?
🏠 Solar for Refrigerator
How many panels to run your fridge on solar.
💧 Solar Hot Tub Calculator
Size a solar system to power your hot tub.
⚙ Solar Bitcoin Mining
Calculate solar system size and savings for crypto mining.
🏊 Solar Pool Pump Calculator
Size a solar system to power your pool circulation pump.
🌿 Solar Grow Light Calculator
Calculate solar panels needed to power indoor grow lights.
🌡 Solar + Heat Pump Savings
Combined savings from switching to heat pump powered by solar.
🍽 Solar Dishwasher Calculator
How many panels to offset your dishwasher.
🔥 Solar Electric Oven Calculator
Solar offset for electric ovens and ranges.
🔥 Solar Induction Cooktop Calculator
Solar offset for induction cooking.
🌿 Solar Cannabis Grow Calculator
Massive energy loads for indoor cannabis cultivation.
🔌 Solar Elevator/Lift Calculator
Building elevator solar offset sizing.
Environmental Impact
Calculate the environmental benefits of going solar.
🌱 Solar Carbon Offset Calculator
How much CO2 does your solar system offset?
🍃 CO2 Savings Calculator
Your solar panels prevent this much carbon emissions.
🌲 Trees Equivalent Calculator
Your solar system = this many trees planted.
🌬 Solar vs Wind
Compare solar panels to wind turbines for your home.
🌾 Agrivoltaics Calculator
Dual-use farming: combine solar panels with crop production.
🌎 Panel Lifecycle CO2
Cradle-to-grave carbon footprint of solar panels.
Tools & Converters
Quick electrical conversions and unit tools.
🔄 Watts to kWh Converter
Convert watts and time to kilowatt-hours.
🔸 Amps to Watts Converter
Quick amps/watts/volts conversion.
⚡ Volts / Amps / Watts Calculator
The electrical triangle — calculate any from the other two.
🚲 Solar E-Bike Calculator
Charge your e-bike, scooter, or golf cart with solar.
🌪 Weather Resilience Calculator
Check wind, hail, and hurricane ratings for your panels.
📐 Panel Layout Planner
Calculate how many panels fit your roof with setbacks.
🌞 Seasonal Production Calculator
Monthly solar output breakdown for 20 US cities.
📋 Permit Timeline Estimator
Estimate your solar permit and PTO timeline by state.
📑 Warranty Comparison Calculator
Compare panel, inverter, and battery warranties side-by-side.
📊 Performance Ratio Calculator
Measure your system's PR against industry benchmarks.
⚡ Capacity Factor Calculator
Calculate your solar farm's capacity utilization rate.
🍃 Soiling Loss Calculator
Estimate production losses from dust and dirt accumulation.
🔌 Racking Weight Calculator
Calculate total dead load of panels and racking system.
🔋 Ballast Calculator
Size concrete ballast for flat roof solar mounts.
📺 Solar Window Calculator
Calculate your daily solar production window by location.
🧭 True South Finder
Magnetic declination correction for accurate panel orientation.
⚡ String Voltage Checker
Temperature-corrected Voc and Vmp check for string sizing.
🌟 Cleaning Schedule Calculator
Optimal panel cleaning frequency by climate.
📊 Mismatch Loss Calculator
Panel mismatch power reduction analysis.
🌓 Shading by Time of Day
Hour-by-hour shade impact analysis.
🔧 PV Labor Hours Calculator
Installer hours estimator for solar projects.
Country-Specific
Solar calculators tailored to your country's incentives, rates, and regulations.
🇺🇸 United States
ITC tax credit, net metering by state, cost by state.
🇦🇺 Australia
Solar rebates, feed-in tariffs, high-insolation sizing.
🇬🇧 United Kingdom
SEG payments, solar grants, UK-specific panel sizing.
🇿🇦 South Africa
Load shedding backup, hybrid inverter sizing, Eskom rates.
🇨🇦 Canada
Provincial incentives, cold-climate optimization.
🇮🇳 India
PM Surya Ghar subsidy calculator.
🇳🇬 Nigeria
NERC band-aware solar sizing.
🇳🇿 New Zealand
Regional buy-back rate comparison.
🇮🇳 PM Surya Ghar Subsidy
India's solar subsidy calculator.
🇿🇦 Load Shedding Solar
Stage-by-stage backup sizing for South Africa.
🇬🇧 Smart Export Guarantee
Compare UK SEG supplier rates.
🇳🇬 DARES Solar Subsidy
Nigeria's $750M solar program calculator.
🇵🇭 Philippines
Meralco rate-based solar calculator.
🇰🇪 Kenya
KPLC tariff solar sizing with off-grid option.
🇵🇰 Pakistan
Load shedding solar calculator with PKR pricing.
🇦🇪 UAE
Shams Dubai program and desert heat sizing.
🇮🇩 Indonesia
PLN tariff-based solar calculator.
🇲🇽 Mexico
CFE tariff and DAC escape solar calculator.
🇧🇷 Brazil
Marco Legal net metering solar calculator.
🇹🇭 Thailand
PEA/MEA tariff solar calculator.
🇻🇳 Vietnam
EVN tariff calculator.
🇪🇬 Egypt
World-class solar resource (Aswan 6.5 PSH).
🇨🇱 Chile
Atacama Desert highest irradiance on Earth.
🇹🇷 Turkey
3,000+ sun hours annually with net metering.
🇲🇦 Morocco
Ouarzazate world-class irradiance — 5.5+ PSH.
🇪🇸 Spain
Autoconsumo solar calculator with Spanish incentives.
🇨🇴 Colombia
Ley 1715 incentive calculator for Colombian solar.
🇬🇷 Greece
Island premium + Exoikonomisi subsidy calculator.
🇯🇵 Japan
FIT + Tokyo solar mandate calculator.
🇩🇪 Germany
EEG feed-in + KfW grants + 0% VAT.
🇸🇦 Saudi Arabia
Vision 2030 solar with 6+ PSH.
🇵🇹 Portugal
Fundo Ambiental + excellent irradiance.
🇮🇹 Italy
Detrazione 50% + Scambio sul Posto.
🇫🇷 France
Prime autoconsommation + obligation d'achat feed-in tariff.
🇰🇷 South Korea
85% government subsidy loans + REC market sizing.
🇵🇱 Poland
Moj Prad 6.0 grant + net-billing prosumer calculator.
🇳🇱 Netherlands
2027 saldering cliff edge solar sizing.
🇮🇪 Ireland
SEAI grant up to €1,800 solar calculator.
🇧🇪 Belgium
Flanders/Wallonia/Brussels tri-region solar calculator.
🇸🇪 Sweden
Grönt avdrag + 4-zone pricing solar calculator.
🇳🇴 Norway
Enova støtte + arctic latitude solar sizing.
🇩🇰 Denmark
Hourly settlement gruppe 6 solar calculator.
🇮🇱 Israel
Two-tier city/non-city tariff solar calculator.
🇨🇿 Czech Republic
Nová zelená úsporám solar subsidy calculator.
🇦🇹 Austria
0% VAT + OeMAG tariff solar calculator.
🇨🇭 Switzerland
Einmalvergütung one-time rebate solar calculator.
🇫🇮 Finland
Arctic latitude + Kotitalousvähennys solar calculator.
🇭🇺 Hungary
Gross metering self-consumption solar calculator.
🇵🇪 Peru
PEN/USD + DS-009 net metering solar calculator.
🇹🇼 Taiwan
20-year FIT guarantee solar calculator.
🇧🇩 Bangladesh
SREDA net metering + IDCOL loans solar calculator.
🇦🇷 Argentina
Ley 27.424 net metering with inflation note.
🇸🇰 Slovakia
Zelená domácnostiam grant solar calculator.
🇷🇴 Romania
Casa Verde Fotovoltaice subsidy solar calculator.
🇪🇪 Estonia
Northern latitude solar sizing with KredEx support.
🇸🇬 Singapore
Property type aware solar calculator for HDB, condo, and landed.
🇲🇾 Malaysia
NEM 3.0 + MyHIJAU GITA solar calculator.
🇧🇬 Bulgaria
NEPR net metering solar calculator.
🇭🇷 Croatia
Coastal high-PSH solar sizing calculator.
🇸🇮 Slovenia
Eco Fund subsidy solar calculator.
🇱🇹 Lithuania
Cumulative Power Account solar calculator.
🇱🇻 Latvia
ALTUM grant up to 50% solar calculator.
🇮🇸 Iceland
Off-grid and marine solar focus calculator.
🇨🇾 Cyprus
Fastest payback in EU solar calculator.
🇭🇰 Hong Kong
FiT scheme generous solar calculator.