ChargeEstimateKit

Sources & Methodology

Written and maintained by ChargeEstimateKit

Last reviewed:

ChargeEstimateKit uses straightforward calculator formulas with values entered by the user. The calculators are meant for educational and planning estimates, not guaranteed billing, safety, installation, or vehicle-specific results.

Pricing data is entered by the user. The current version does not use a live station price feed and does not include a country, city, or charging-network price database. For cost estimates, use the current price shown by your utility bill, charging app, station screen, or electricity plan.

The reference links below support general charging terminology, charging levels, home and public charging context, and the reality that electricity prices vary by location, provider, fuel costs, infrastructure, demand, taxes, and other local factors. They are background references for user understanding, not live data feeds used by the calculators.

Data policy

ChargeEstimateKit does not use a live price feed, utility tariff database, vehicle specification database, or charging network database. Users should enter the rate shown by a utility bill, charging app, station screen, vehicle dashboard, or electricity plan.

Source scope

Reference links are used for general charging terminology and background. Some references are U.S.-focused, including DOE AFDC and EIA pages. Manufacturer pages are included only as examples of vehicle-specific charging documentation; they are not a complete vehicle database. The calculators can still be used internationally because users enter their own rates, units, and efficiency values.

Review schedule

The target review cadence is quarterly or when a major reference, formula, charging convention, or safety boundary changes. Each reference below includes the date its page and intended use were last checked. A checked date means the link and relevant context were reviewed; it does not turn a reference into a live data feed.

Class 1: user-entered arithmetic

Calculator outputs apply the formulas displayed on each page to values entered by the visitor. This arithmetic does not need an external citation, and an official source should not be read as validating a visitor's particular inputs or result.

Class 2: official context

  • Government and national-laboratory references support only the claims stated in their support scope.
  • Manufacturer references illustrate where to verify that manufacturer's documentation and are not generalized to every EV.
  • Every reference records what it does not support so a source cannot be stretched to cover a result, price, installation, or vehicle it never evaluated.

Class 3: site planning assumptions

Editable defaults and worked examples, including 90% charging efficiency, example charger power, prices, fees, reserve percentages, and illustrative curve heights, are site-selected planning assumptions. They are not market averages or vehicle specifications, and no loosely related citation is attached to make them appear sourced.

What these calculators do not do

  • They do not provide billing guarantees.
  • They do not check live station prices.
  • They do not select breaker size.
  • They do not approve wiring, permits, installation, load calculations, or code compliance.
  • They do not verify vehicle-specific charging limits.

Core formulas

  • EV Charging Time: energy needed (kWh) = battery capacity (kWh) x (target % - current %) / 100
  • EV Charging Time: charging hours = energy needed (kWh) / (charger power (kW) x efficiency)
  • EV Charging Cost: wall energy (kWh) = energy added (kWh) / efficiency
  • EV Charging Cost: cost = wall energy (kWh) x electricity price per kWh + session fee
  • Home vs Public Cost: session cost = energy added / efficiency x price per kWh + fixed fees
  • Home vs Public Cost: monthly mix cost = monthly wall energy split by home and public charging share
  • kWh to Range: range = available energy x vehicle efficiency
  • kWh to Range: planning range = range after reserve and condition buffer
  • kWh to Range: trip surplus or shortfall = planning range - planned trip distance
  • Charger Power: single-phase kW = volts x amps x power factor / 1000
  • Charger Power: three-phase kW = volts x amps x sqrt(3) x power factor / 1000
  • Battery Charging Time: Wh = volts x Ah
  • Battery Charging Time: Wh = volts x mAh / 1000
  • Battery Charging Time: charging hours = battery Wh / (charger W x efficiency)

Reference library

Charging fundamentals

Home and public charging

Electricity pricing

Charging behavior research

Charging efficiency context

Efficiency and range context

Battery safety

Vehicle-specific examples

  • Tesla Support: Supercharging
    Use
    Manufacturer-specific example of charging rate, temperature, state-of-charge, and fee documentation.
    Supports
    An example of one manufacturer's documentation for its own vehicles, charging behavior, and network fee categories.
    Does not support
    It does not establish behavior, charging curves, pricing, or specifications shared by every electric vehicle or network.
    Used on
    Reference library only; not attached to a general claim.
    Source checked
  • Ford: Mustang Mach-E Official Vehicle Page
    Use
    Manufacturer-specific example of where to cross-check model documentation.
    Supports
    An example of an official manufacturer page used to cross-check model-specific specifications and documentation.
    Does not support
    It does not establish charging behavior, battery capacity, or performance shared by every electric vehicle.
    Used on
    Reference library only; not attached to a general claim.
    Source checked

Validation and corrections

Published examples are checked against the displayed formulas and representative inputs on the Validation Test Cases page. If a source moves, a formula result changes, or a safety boundary is unclear, send the page URL and supporting reference through the Contact page. A correction is reviewed before the content date is updated.