Pick your vehicle or enter specs manually, add your driving and panel details, choose a charger, then calculate. Formula: Continuous Load = Charger Amps × 1.25, checked against your panel's available capacity.
Your Vehicle
Optional — select your vehicle to auto-fill its onboard (AC) charger limit and usable battery capacity below, or skip this and enter your own values.
Onboard (AC) charger limits and battery figures are typical published specifications per trim and may vary by model year, options, and software updates. Figures noted as unavailable have not been independently confirmed against manufacturer documentation this session. Always verify your exact vehicle's specs against your owner's manual or manufacturer's site.
Your Driving Needs
Not sure what a field means? Tap the ⓘ next to its label.
Panel & Charger Details
Your panel's main breaker rating is on the largest breaker in your panel, usually labeled MAIN.
Not everyone knows their wire-run distance in advance — leave this closed and the results skip voltage drop, or open it and check whether a longer run needs a larger wire.
Your Results
Results are for reference and estimation only — not a permit-ready NEC calculation. See full disclaimer below.
A deeper look at what actually determines a home EV charger's size — written for installation planning and general reference alike.
Level 1 vs. Level 2 vs. Level 3
Level 1 uses a standard 120V household outlet at 12–16A, delivering roughly 3–5 miles of range per hour with no electrical work required — often enough for light daily driving. Level 2 uses a dedicated 240V circuit at 16–80A, delivering roughly 15–40+ miles per hour depending on amperage, and is what most homeowners install. Level 3, or DC fast charging, requires 480V three-phase commercial service and is not a home charging option.
Why Bigger Isn't Always Better
The EV charger market pushes 48A units as the standard, but a smaller charger — 24A or 32A — fully replenishes most daily driving overnight and pairs with a smaller breaker, which can be the difference between a simple circuit addition and a full panel upgrade. Match the charger to your driving pattern and your vehicle's onboard charger limit, not just the biggest number on the shelf.
Continuous Load and the 125% Rule
NEC 625.42 classifies EV charging as a continuous load — one expected to run at maximum current for three hours or more — and NEC 210.20(A) requires the circuit's conductors and overcurrent protection to be sized at 125% of that load. That's why a 48A charger is paired with a 60A breaker rather than a 48A one: the extra margin accounts for sustained current draw during a long charging session.
GFCI Protection
NEC 625.54 requires GFCI protection for cord-and-plug connected EVSE — any charger plugged into a NEMA 14-50 or similar outlet needs a GFCI breaker at the panel. Hardwired units like a Tesla Wall Connector or a hardwired ChargePoint Home Flex commonly include built-in GFCI or CCID protection that satisfies this requirement, but always verify against the specific unit's installation instructions.
When You'll Likely Need a Panel Upgrade
A panel upgrade becomes likely when your main breaker is 100A or smaller and you're adding a 40A+ charger, your existing load already runs high relative to your panel rating, you have no available breaker slots, or you're adding the charger alongside other large loads like a hot tub or workshop. Most 200A panels in homes built after 2000 have enough headroom for a Level 2 charger without an upgrade.
Named Chargers Are Reference Only
Product names in the Charger selector are shown to help you match a common unit's published spec sheet, not as a recommendation or endorsement. SolarEVCalculators.com is not affiliated with or endorsed by any manufacturer listed, and product specs can change between model years — always confirm against the unit's current manufacturer documentation before purchase or installation.