Our Data Methodology

Understanding how we calculate vehicle costs and where our data comes from

At LeaseFinder.ai, we believe in transparency. That's why we're sharing our complete methodology for calculating vehicle costs and the sources of our data. Our goal is to provide the most accurate, comprehensive comparison of vehicle lease costs possible, including energy costs that are often overlooked in traditional lease comparison tools.

This page details how our Total Cost of Ownership (TCO) calculator works, what factors we consider, and how we source and validate our information.

Total Cost of Ownership Calculation

Our TCO calculator considers the following key components to provide a complete picture of what it costs to lease and operate a vehicle:

Lease Payment Components

  • Capitalized Cost (Cap Cost)

    The negotiated vehicle price after any rebates, incentives, or discounts.

  • Residual Value

    The projected value of the vehicle at lease end, typically expressed as a percentage of MSRP.

  • Money Factor

    The lease equivalent of an interest rate. We convert this to APR for easier comparison (Money Factor × 2400 = APR%).

  • Lease Term

    The duration of the lease agreement, typically 24, 36, or 48 months.

  • Down Payment & Fees

    Includes down payment, acquisition fee, disposition fee, and any other upfront costs amortized over the lease term.

Energy Cost Components

  • Fuel Costs (ICE & Hybrid Vehicles)

    Calculated using EPA MPG ratings, regional fuel prices, and user-provided annual mileage.

  • Electricity Costs (EV & PHEV)

    Based on vehicle efficiency (kWh/100 miles), regional electricity rates, and annual mileage.

  • PHEV Energy Mix

    For plug-in hybrids, we calculate cost based on electric range, assuming one full charge per day before switching to fuel.

  • ZIP Code Adjustment

    Energy costs are adjusted based on the user's ZIP code to reflect local gas and electricity prices.

Monthly Cost Formula

Monthly Total Cost = Monthly Lease Payment + Monthly Energy Cost

Monthly Lease Payment = (Cap Cost - Residual Value) / Lease Term + (Cap Cost + Residual Value) × Money Factor

Monthly Energy Cost (ICE) = (Monthly Miles ÷ MPG) × Fuel Price per Gallon

Monthly Energy Cost (EV) = (Monthly Miles × kWh per Mile) × Electricity Price per kWh

Monthly Energy Cost (PHEV) = [(Daily Electric Miles × Days per Month) × Electricity Cost] + [(Remaining Monthly Miles) × Fuel Cost]

Vehicle Classification Methodology

We categorize vehicles based on propulsion type to ensure accurate energy cost calculations:

ICE Vehicles

Gas/Diesel

Traditional internal combustion engine vehicles that run exclusively on gasoline or diesel fuel. Energy costs calculated based on MPG and fuel prices.

BEV/EV

Electric

Battery electric vehicles that run solely on electricity. Energy costs calculated based on kWh/100mi efficiency and electricity rates.

PHEV

Plug-in Hybrid

Plug-in hybrid vehicles that can run on electricity for a limited range before switching to gasoline. Costs based on electric range, MPG, and daily driving patterns.

HEV (Hybrid)

Hybrid

Hybrid electric vehicles that self-charge but cannot be plugged in. Costs calculated based on improved MPG compared to ICE vehicles.

MHEV

Mild Hybrid

Mild hybrid vehicles with small electric assistance but primarily gas-powered. Costs calculated with a slight efficiency improvement over standard ICE vehicles.

Data Sources & Frequency

We pull data from the following sources to ensure our calculations are as accurate as possible:

Vehicle Specifications

Data on vehicle MSRP, MPG, kWh/100mi, electric range, and other specifications.

Edmunds APIEPA FuelEconomy.govManufacturer Websites

Updated weekly

Fuel & Electricity Prices

Regional data on gasoline, diesel, and electricity prices by ZIP code.

ZylaLabs Gas Price Locator APIUS Energy Information AdministrationDepartment of Energy

Updated daily

Lease Terms & Incentives

Money factors, residual values, and available manufacturer incentives.

Manufacturer Finance WebsitesDealer NetworksUser-Submitted Spreadsheets

Updated monthly

Maintenance Estimates

Scheduled maintenance costs by make, model, and vehicle type.

RepairPalEdmunds True Cost to OwnManufacturer Service Schedules

Updated quarterly

Data Verification & Quality Control

To ensure accuracy, we employ the following verification processes:

  • Cross-Validation: Vehicle specifications are cross-checked across multiple sources to ensure consistency.
  • Human Review: Unusual data points are flagged for manual review by our automotive experts.
  • Weekly Audits: Random sample audits verify data accuracy and identify potential issues.
  • User Feedback: We incorporate user-reported data discrepancies to continuously improve accuracy.

Limitations & Assumptions

While we strive for the highest accuracy, there are some limitations and assumptions in our calculations:

  • For PHEVs, we assume one full charge per day before switching to gasoline.
  • We use EPA combined MPG/MPGe ratings, which may differ from real-world performance.
  • Regional variations in lease terms and incentives may not be fully captured.
  • Some manufacturer incentives may be time-limited and subject to change.
  • We do not factor in potential savings from home charging equipment installation for EVs.
  • Insurance costs vary widely by driver and are therefore not included in our calculator.

Methodology last updated: May 15, 2025

If you have questions about our methodology or suggestions for improvement, please contact us.