Straight answers about how RealEVRange works, why our numbers differ from manufacturers, and what to do if something looks wrong.
Why is your range estimate lower than the manufacturer? ▾
EPA and WLTP figures are measured in controlled lab conditions — constant temperature, smooth road, no AC, specific low-speed cycles. Our engine models real highway conditions at 65 mph with real air drag. That's almost always lower, and almost always closer to what you'll actually see on the road.
What data does the physics engine use? ▾
Five primary parameters per vehicle: weight_kg, cx (drag coefficient), frontal_area_m2, battery_net_kwh, and tire_width_mm. From these we compute aerodynamic drag, rolling resistance, and drivetrain losses. All inputs are sourced from manufacturer spec sheets and regulatory filings.
How accurate is the Used EV Battery Audit? ▾
Our SOH (State of Health) model uses brand-specific degradation coefficients derived from fleet data (Geotab, Recurrent). Accuracy is within ±3–5% for most vehicles. The model is more accurate for Tesla, Hyundai/Kia, and Nissan than for rarer brands with less field data.
What is the calibration_factor? ▾
A per-car correction applied to the raw physics output to match the vehicle's actual EPA highway range. It captures physical phenomena not in the base model — parasitic drivetrain losses, optimized regen, active aero. Values typically range from 0.70 (trucks) to 1.10 (very efficient sedans). It's not a magic number — every value is justified by real-world data.
How does the live weather calculation work? ▾
Cold air is denser, which increases aerodynamic drag. Cold temperatures also raise battery internal resistance and force the cabin heater to draw power. We call the OpenWeatherMap API for your city's live temperature, recalculate air density (ρ), and apply a thermal penalty to the range estimate.
I found wrong data for a car — what do I do? ▾
Use the contact form below and select "Wrong car data" as the category. Include the car name, the incorrect field (e.g., battery capacity, weight), and a source link if you have one. We verify and update within 48 hours. Your name will never be published.
What does the Transparency Score mean? ▾
RealEVRange Estimate ÷ Manufacturer Claim × 100. A score of 85%+ means the manufacturer is relatively honest. 75–84% is a moderate gap. Below 75% means significant overstatement vs real highway conditions.
Is my data shared with anyone? ▾
No. We don't sell data, show ads, or track you for profit. The only third-party calls are OpenWeatherMap (for temperature) and Stripe (for the Used EV Audit report ($1.99)). See our
Privacy Policy for full details.
Do you have a mobile app? ▾
Not yet. The site is fully mobile-optimized and works in any browser. A native app is on the roadmap — if you'd like to be notified when it launches, send us a message below with "App waitlist" in the subject.
Can I use your data in my own project? ▾
Contact us with your use case. Personal and non-commercial use is generally fine with attribution. Commercial or API-level access requires a data licensing agreement. We don't allow scraping or automated harvesting of our database.