How to Calculate EV Charging Cost per Mile or per kWh
Last updated: October 2025
Master the art of calculating your electric vehicle charging costs with comprehensive formulas, real-world examples, and money-saving strategies.
Cost per mile = electricity price ÷ (mi/kWh × charging efficiency).
If you track kWh/100 miles instead: Cost per mile = price × (kWh/100 mi) ÷ (100 × efficiency).
Typical Level-2 charging efficiency is ~0.88–0.95 (use 0.90 as a default). DC fast charging prices are usually billed per kWh delivered, so you can use efficiency = 1.00 for a simple estimate.
- •Your electricity price ($/kWh). If your bill shows ¢/kWh, divide by 100. Note off-peak vs peak if you're on TOU.
- •Your efficiency (either mi/kWh or kWh/100 mi). Use your car's trip meter or a recent average.
- •Charging efficiency (home Level-2): default 0.90 unless you have better data.
Cost per mile = Price ($/kWh) ÷ (mi/kWh × Efficiency).
Example: $0.15 ÷ (3.5 × 0.90) ≈ $0.048/mi (≈4.8¢/mi).
Cost per mile = Price × (kWh/100 mi) ÷ (100 × Efficiency).
Example: $0.20 × 28 ÷ (100 × 0.90) ≈ $0.062/mi (≈6.2¢/mi).
- •Home off-peak $0.15/kWh, 3.5 mi/kWh, 0.90 efficiency → ≈4.8¢/mi.
- •DC fast $0.55/kWh, 3.0 mi/kWh → ≈18.3¢/mi.
- •Blended month (70% home at 5.9¢/mi, 30% DC at 17.2¢/mi) → ≈9.3¢/mi overall.
Monthly charging cost ≈ (miles per month) × (cost per mile).
Example: 1,000 mi × 9.3¢/mi ≈ $93/month.
Step 1: Find Your Electricity Rate
Determine your cost per kWh from your utility bill or charging network.
Common Rates:
- • Home charging: $0.10-$0.30/kWh (varies by location and time)
- • Public Level 2: $0.20-$0.40/kWh
- • DC Fast charging: $0.25-$0.60/kWh
- • Tesla Supercharger: $0.25-$0.50/kWh
Step 2: Account for Charging Efficiency
Not all electricity makes it to your battery due to conversion losses.
• Home AC charging: Base Rate × 1.10 (10% loss)
• DC Fast charging: Base Rate × 1.05 (5% loss)
Step 3: Find Your Vehicle's Efficiency
Check your EPA rating or calculate from real-world driving data.
How to Calculate:
Example: 300 miles ÷ 75 kWh = 4.0 mi/kWh
Step 4: Calculate Cost per Mile
Apply the final formula to get your cost per mile.
Example: (1 ÷ 4.0 mi/kWh) × $0.132/kWh = $0.033/mile
Home Charging ($0.12/kWh)
| Vehicle | Efficiency | Cost per Mile | Cost per 100 Miles |
|---|---|---|---|
| Tesla Model 3 | 4.1 mi/kWh | $0.032 | $3.20 |
| Nissan Leaf | 3.5 mi/kWh | $0.038 | $3.77 |
| Ford F-150 Lightning | 2.1 mi/kWh | $0.063 | $6.29 |
Tesla Model 3
Nissan Leaf
Ford F-150 Lightning
Public DC Fast Charging ($0.35/kWh)
| Vehicle | Cost per Mile | vs Home Charging | vs Gasoline* |
|---|---|---|---|
| Tesla Model 3 | $0.090 | +181% | -25% |
| Nissan Leaf | $0.105 | +177% | -13% |
| Ford F-150 Lightning | $0.175 | +178% | -30% |
Tesla Model 3
Nissan Leaf
Ford F-150 Lightning
*Gasoline comparison based on $3.50/gallon and comparable vehicle MPG
Variable Costs
- •Time-of-use rates: Off-peak can be 50% cheaper
- •Seasonal variations: Summer rates often higher
- •Demand charges: Some utilities charge for peak usage
- •Network pricing: Different charging networks have different rates
Efficiency Factors
- •Weather: Cold reduces efficiency by 20-40%
- •Driving style: Highway vs city driving affects consumption
- •Vehicle load: Extra weight increases energy use
- •Climate control: Heating/AC can add 10-30% to costs
Speed and weather, HVAC use, tires, roof racks, hills, and higher average speeds reduce mi/kWh. Off-peak TOU pricing can lower cost. Cold/heat and high states of charge can change efficiency from one trip to another.
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