# Panel Load Calculator: Is 100 or 200 Amps Enough? Page: https://electricsandro.com/tools/panel-load-calculator/ Business: Electric Sandro | (571) 402-2540 | Quantico, VA Updated: 2026-11-10 [Home](/) / [Tools](/tools/) / Panel Load Calculator # Panel Load Calculator By the NEC standard method, a gas-heated home of 1,500 to 2,000 sq ft often estimates at about 70 to 90 amps. Electric heat, an electric range or an EV charger can push it past 150 amps, so 200 amp service is typical for all-electric homes. What do you want to know? My panel or service size New appliance Charger setting (amps) New appliance (watts, from its label) How should we count your current load? Highest 15-minute demand, last 12 months (kW) Living area (sq ft) Kitchen and laundry 20 A circuits Heating Electric heat (kW) AC or heat pump outdoor unit (watts, 0 if none) Electric range, or cooktop plus oven (kW, 0 if gas) Electric dryer (watts, 0 if gas) Electric water heater (watts, 0 if gas) Dishwasher (watts) Disposal (watts) Built-in microwave (watts) Well pump (watts) Hot tub or spa (watts) EV charger you have now **About 146 amps** This is an estimate for planning. Electrical work needs an expert electrician and, in most places, a permit. Planning electrical panel upgrades in Northern Virginia? An expert electrician can check your home. [Electrical Panel Upgrades](/services/panel-upgrade/) [(571) 402-2540](tel:+15714022540) ## How the calculator works The calculator follows the standard method for homes in [NFPA 70, the National Electrical Code (NEC)](https://www.nfpa.org/codes-and-standards/nfpa-70-standard-development/70), Article 220 Part III, 2023 edition. It adds up each kind of load the way the code counts it, then divides by 240 volts to get amps. Lights and general outlets count as 3 volt-amperes (VA) per square foot of living area. Each kitchen and laundry circuit adds 1,500 VA. That group gets a demand factor: the first 3,000 VA at 100% and the rest at 35%, because not every light and outlet is on at once. Big appliances follow their own rules. A range up to 12 kW counts as 8,000 VA. A dryer counts as at least 5,000 VA. Four or more fixed appliances, like a water heater, dishwasher and disposal, count at 75%. An EV charger counts as 7,200 VA or its nameplate, whichever is larger. Heating and cooling do not run at the same time, so only the larger one counts, plus 25% of the AC or heat pump compressor when it is on that side. The result is an estimate in amps with a plain label, like 100 A likely enough, 100 A may be tight, or 200 A typical. A full load calculation by an electrician decides what your home needs. ## What changes the answer most Electric heat is the biggest lever. A 10 kW electric furnace adds about 42 amps by itself. A heat pump with backup heat strips counts the compressor and the strips together, because they run together on cold days. Next come the EV charger, the range and the dryer. A 48 amp charger adds 11,520 VA, about 48 amps. Gas heat, a gas range, a gas dryer and a gas water heater keep the number low. Square feet matter less than most people think, because of the 35% demand factor. ## Can my panel handle it? Pick this mode to test one new appliance against the panel you have. You can count your current load two ways. The first uses your home details and the same standard method. The second uses your utility's highest 15-minute demand from the last 12 months. NEC 220.87 lets an electrician use that number times 125% for an existing home. The answer is yes when the total stays under 80% of the panel rating, maybe from 80% to 100%, and needs a load calculation when it goes over. The 80% line is a planning margin, not a code limit. When the answer is maybe, a load management device or a lower EV charger setting often helps. ## When to call an expert electrician Call before you add a large load: an EV charger, a heat pump, a hot tub, an electric range or a new addition. Also call if breakers trip often, the panel feels warm, or the main breaker is smaller than you thought. An electrician checks the real nameplates, the service conductors, the meter base and the panel's open spaces. Utility demand data, the optional method in NEC 220.82, or a load management device can show room that this estimate does not. ## The code basis The math uses the 2023 NEC. Many states and towns still use the 2020 NEC or an older edition, so your local rules may differ. The main numbers are the same in 2020 and 2023, but the sections moved: the 3 VA per square foot rule went from Table 220.12 to 220.41, and the demand factor table went from Table 220.42 to Table 220.45. The EV charger rule in 220.57 is new in 2023. NFPA lets anyone read the code for free online through its [free access page](https://www.nfpa.org/freeaccess). A permit and an inspection apply to service and panel work in most places. How the standard method counts each load (NEC 2023; 2020 number in brackets where it moved) Load How it counts NEC section Lights and general outlets 3 VA per sq ft of living area 220.41 \[Table 220.12\] Kitchen and laundry circuits 1,500 VA each (at least 2 kitchen and 1 laundry) 220.52 Demand factor on the two rows above First 3,000 VA at 100%, up to 120,000 VA at 35%, the rest at 25% Table 220.45 \[Table 220.42\] Fixed appliances (water heater, dishwasher, disposal, built-in microwave, well pump) Nameplate; 75% when there are 4 or more 220.53 Clothes dryer 5,000 VA or nameplate, whichever is larger 220.54 Range, or cooktop plus wall oven 8.75 kW or less: 80%. Up to 12 kW: 8,000 VA. Over 12 kW: add 5% for each kW over 12 220.55 Electric space heat 100% of nameplate 220.51 Heating and cooling Only the larger one counts 220.60 Largest motor (AC or heat pump compressor) Add 25% of it 220.50, 430.24 EV charger 7,200 VA or nameplate, whichever is larger 220.57 \[new in 2023\] Amps Total VA divided by 240 V 220.5 ## Worked example: 2,000 sq ft home with electric heat 1. Lights and outlets: 2,000 sq ft x 3 VA = 6,000 VA. Add 3 kitchen and laundry circuits x 1,500 VA = 4,500 VA. Total 10,500 VA. 2. Demand factor: first 3,000 VA at 100% = 3,000. The other 7,500 VA at 35% = 2,625. Subtotal 5,625 VA. 3. Range, 12 kW: counts as 8,000 VA. Dryer, 5,000 W: counts as 5,000 VA. 4. Fixed appliances: water heater 4,500 + dishwasher 1,200 + disposal 800 = 6,500 VA. Only 3 items, so no 75% factor. 5. Heating 10,000 VA (electric furnace) is larger than cooling 5,000 VA (AC), so heating counts: 10,000 VA. 6. Total: 5,625 + 8,000 + 5,000 + 6,500 + 10,000 = 35,125 VA. Divide by 240 V = about 146 amps. 7. Label: 150 A or 200 A service. A 100 A service is too small by this estimate. ## Panel Load Calculator questions Short answers to common questions. ![Zappy holding a calculator](/brand/zappy/zappy-electric-sandro-mascot-calculator-300.webp) How many amps does a house need? It depends on what runs on electricity. By the NEC standard method, a gas-heated home often estimates under 100 amps. Homes with electric heat, an electric range and an EV charger often estimate at 150 to 200 amps or more. The code sets 100 amps as the minimum service for a one-family home (NEC 230.79). Is 100 amp service enough for an EV charger? Sometimes. By the standard method, a gas-heated home on 100 A service is often near the limit with a 24 A or 32 A charger, and over it with a 48 A charger. Utility demand data (NEC 220.87) or a load management device often shows room. Use the Can my panel handle it mode to check your home. Why is this number higher than what my house really uses? The standard method counts each appliance at its code value, as if most of them run at once. Real use is often lower. That is why NEC 220.87 lets an electrician use 12 months of utility demand data for an existing home, and why the optional method in 220.82 often gives a smaller number. What is the difference between the standard and optional method? The standard method (Article 220 Part III) uses a demand factor for each type of load. The optional method (220.82) is only for single homes: it takes the first 10 kVA of most loads at 100% and the rest at 40%, then adds heating or cooling. An electrician can use either one. Does a heat pump need 200 amp service? Not always. A heat pump replacing a gas furnace and AC adds the compressor, and the backup heat strips add a lot more. A 10 kW strip heater alone is about 42 amps. Enter your heat pump and strip size to see the estimate. Is this an official load calculation? No. It is an estimate for planning. An expert electrician uses the real nameplate ratings and the code your town uses, and the permit office reviews the result. **Sources:** [NFPA 70, National Electrical Code (2023), Article 220 Parts III and IV](https://www.nfpa.org/codes-and-standards/nfpa-70-standard-development/70) · [NFPA free access to codes and standards](https://www.nfpa.org/freeaccess) · [U.S. Department of Energy, Alternative Fuels Data Center: charging at home](https://afdc.energy.gov/fuels/electricity-charging-home). Last updated November 7, 2026. ![Zappy answering the phone for Electric Sandro](/brand/zappy/zappy-electric-sandro-mascot-takes-a-call-300.webp) ## Need an electrician you can trust? Tell us about the job. We call you back, explain the work in plain words and set a time. [Get a quote](/contact/#quote) [Call now](tel:+15714022540) ```json {"@context":"https://schema.org","@type":"Electrician","@id":"https://electricsandro.com/#business","name":"Electric Sandro","url":"https://electricsandro.com/","image":"https://electricsandro.com/images/electrician-installing-ceiling-light-fixture-modern-home.webp","logo":"https://electricsandro.com/brand/logo-512.png","address":{"@type":"PostalAddress","addressLocality":"Quantico","addressRegion":"VA","addressCountry":"US","postalCode":"22134"},"areaServed":[{"@type":"Place","name":"Northern Virginia"},{"@type":"AdministrativeArea","name":"Prince William County, VA"},{"@type":"AdministrativeArea","name":"Stafford County, VA"},{"@type":"AdministrativeArea","name":"Fairfax County, VA"},{"@type":"AdministrativeArea","name":"Loudoun County, VA"},{"@type":"AdministrativeArea","name":"Arlington County, VA"},{"@type":"AdministrativeArea","name":"City of Alexandria, VA"},{"@type":"AdministrativeArea","name":"City of Manassas, VA"}],"telephone":"+1-571-402-2540","email":"info@electricsandro.com","openingHours":"Mo-Fr 07:00-17:00"} ``` ```json {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://electricsandro.com/"},{"@type":"ListItem","position":2,"name":"Tools","item":"https://electricsandro.com/tools/"},{"@type":"ListItem","position":3,"name":"Panel Load Calculator","item":"https://electricsandro.com/tools/panel-load-calculator/"}]} ``` ```json {"@context":"https://schema.org","@type":"SoftwareApplication","name":"Panel Load Calculator","description":"Free panel load calculator. Estimate your home's load in amps with the NEC standard method, and check if your panel can handle an EV charger or new appliance.","url":"https://electricsandro.com/tools/panel-load-calculator/","applicationCategory":"UtilitiesApplication","operatingSystem":"Any","offers":{"@type":"Offer","price":"0","priceCurrency":"USD"},"publisher":{"@id":"https://electricsandro.com/#business"}} ``` ```json {"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"How many amps does a house need?","acceptedAnswer":{"@type":"Answer","text":"It depends on what runs on electricity. By the NEC standard method, a gas-heated home often estimates under 100 amps. Homes with electric heat, an electric range and an EV charger often estimate at 150 to 200 amps or more. 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