EV Charge Time & Cost Estimator
Calculate electric vehicle charging time and cost for any charger type. Enter values for instant results with step-by-step formulas.
Formula
Charge Time = (Battery × (Target% - Current%) / Efficiency) / Charger Power
Energy needed is battery capacity times charge percentage difference, adjusted for charging efficiency losses, then divided by charger power (kW) for time in hours.
Worked Examples
Example 1: Daily Commute Charge
Problem:Tesla Model 3 (75 kWh), charge from 30% to 80% on Level 2 (7.2kW) at home, $0.11/kWh, 4.0 mi/kWh efficiency.
Solution:Charge needed: 75 × (80-30)% = 37.5 kWh With 90% efficiency: 37.5 / 0.9 = 41.7 kWh Time: 41.7 / 7.2 = 5.8 hours Cost: 41.7 × $0.11 = $4.59 Miles added: 37.5 × 4.0 = 150 miles Cost/mile: $0.11 / 4.0 = $0.028 Gas equivalent (30 MPG, $3.50): $17.50 Savings: $12.91 (74%)
Result:5.8 hours | $4.59 | 150 miles | 74% savings vs gas
Example 2: Road Trip DC Fast Charge
Problem:Ford Mustang Mach-E (88 kWh), 15% to 80% at Electrify America (150kW), $0.43/kWh, 3.0 mi/kWh.
Solution:Charge needed: 88 × (80-15)% = 57.2 kWh With 85% DC efficiency: 57.2 / 0.85 = 67.3 kWh Time: 67.3 / 150 = 0.45 hours = 27 minutes Cost: 67.3 × $0.43 = $28.94 Miles added: 57.2 × 3.0 = 172 miles Cost/mile: $28.94 / 172 = $0.17 Note: DC fast is 5x more expensive than home but necessary for road trips
Result:27 minutes | $28.94 | 172 miles | Convenience premium
Example 3: Overnight Full Charge
Problem:Chevy Bolt (66 kWh), 10% to 100% on Level 2 (11kW), time-of-use rate $0.08/kWh (11pm-6am), 4.0 mi/kWh.
Solution:Charge needed: 66 × 90% = 59.4 kWh With 92% efficiency: 59.4 / 0.92 = 64.6 kWh Time: 64.6 / 11 = 5.9 hours Cost: 64.6 × $0.08 = $5.17 Miles added: 59.4 × 4.0 = 238 miles Cost/100 miles: $5.17 / 2.38 = $2.17 Time-of-use savings vs flat rate ($0.14): Flat: 64.6 × $0.14 = $9.04 Savings: $3.87 (43%)
Result:5.9 hours | $5.17 | 238 miles | TOU saves 43%
Frequently Asked Questions
How long does it take to charge an EV?
Varies by charger: Level 1 (120V): 8-24 hours for full charge. Level 2 (240V): 4-8 hours. DC Fast: 20-60 minutes to 80%. Superchargers: 15-30 minutes to 80%. Battery size and starting charge level affect time significantly.
How much does it cost to charge an EV?
Home charging: $0.10-0.20/kWh = $8-15 for full charge. Public Level 2: $0.20-0.35/kWh. DC Fast: $0.30-0.50/kWh. Superchargers: $0.25-0.40/kWh. A typical 300-mile charge costs $10-20 at home, $25-45 at DC fast chargers.
Is home charging cheaper than gas stations?
Yes, significantly. EV: $0.03-0.05/mile at home rates. Gas car (30 MPG at $3.50/gal): $0.12/mile. EVs cost 60-75% less to fuel. Public DC fast charging narrows but doesn't eliminate the savings.
Should I charge every night?
Not necessarily. Unlike phones, EV batteries prefer staying between 20-80%. Charge when convenient or when below 30%. Plugging in nightly is fine if you set a charge limit (80% for daily, 100% for trips).
What is Level 1, 2, and DC fast charging?
Level 1: Standard 120V outlet, 3-5 miles/hour. Level 2: 240V (dryer outlet), 12-30 miles/hour. DC Fast: 480V commercial, 3-20 miles/minute. Higher levels require special equipment and cost more to install/use.
How do I calculate EV cost per mile?
Formula: Electricity rate ($/kWh) ÷ Efficiency (miles/kWh) = $/mile. Example: $0.12/kWh ÷ 3.5 mi/kWh = $0.034/mile. Compare to gas: $3.50/gal ÷ 30 MPG = $0.117/mile.