One electric car. Three range numbers. Sometimes four. WLTP, EPA, and CLTC are standardized lab tests - not lies, but not your commute either.
If you have ever wondered why a Chinese-market car claims 700 km while the European version shows 480 km for "the same" model, this guide is for you.
Key takeaways
- EPA (U.S.) is generally the most conservative - closest to cautious real-world planning for many drivers.
- WLTP (Europe and others) is higher than EPA but more realistic than CLTC.
- CLTC (China) is typically the most optimistic - great for showroom brochures, risky for road-trip math without adjustment.
- Real-world range depends on speed, temperature, wheels, and HVAC more than the label.
- Rule of thumb: plan on 70-75% of the rated number for highway-heavy driving unless you have owner data saying otherwise.
The three main tests
| Test | Used in | Character | Typical vs EPA |
|---|---|---|---|
| EPA | United States | Includes highway and city cycles; adjusts downward with correction factors | Baseline |
| WLTP | EU, UK, many global markets | Four phases, higher average speeds than old NEDC | Often ~10-20% higher than EPA |
| CLTC | China | Includes more low-speed urban driving, less aggressive correction | Often ~20-25% higher than EPA |
Automakers must use the official cycle for the market they sell in. That is why global press releases look inconsistent - they are quoting different rulers.
Why CLTC looks so high
China's CLTC cycle spends more time at lower speeds where EVs are efficient. Highway cruising - where aerodynamic drag kills range - is underweighted compared to how many Western road trips work.
Example context: The Xiaomi SU7 is often quoted around 700 km CLTC on base trims. That is a valid China-market figure. It is not the number you should paste into a U.S. road-trip planner without conversion.
WLTP in plain English
WLTP replaced the old NEDC test in Europe and is now the standard range label on most EU spec sheets. It is more realistic than NEDC was, but still a lab test:
- Assumes mild conditions
- Does not include extreme cold with cabin heat blasting
- Cannot predict your 75 mph motorway habit
Still, WLTP is a reasonable planning start for European buyers if you apply a highway discount.
EPA: the cautious American number
EPA ratings include adjustment factors meant to reflect real-world use more closely than older tests. That is why American EV forums often say "I beat EPA" in city driving but "I miss EPA" on winter highways.
If you are American, start with EPA and adjust:
| Condition | Adjustment |
|---|---|
| Mild city commuting | Often near EPA or better |
| 70+ mph highway | Subtract 15-25% |
| Winter with heat | Subtract 20-30% temporarily |
| Mountain driving | Depends - regen helps downhill, hurts uphill |
How to compare cars fairly
- Compare ratings from the same test cycle only.
- If you only have CLTC and need EPA-ish planning, many analysts use CLTC x 0.65-0.75 as a rough highway-heavy estimate - not official, but better than raw CLTC.
- Check wheel size and trim - big wheels can shave meaningful range.
- Search owner forums and long-term tests for your exact trim.
A practical planning formula
Planning range - rated range × use-case factor
Suggested use-case factors (starting points, not guarantees):
| Use case | Factor on WLTP | Factor on EPA |
|---|---|---|
| City / mixed mild | 0.85-0.95 | 0.90-1.00 |
| Mixed with highway | 0.75-0.85 | 0.80-0.90 |
| Fast highway winter | 0.60-0.75 | 0.65-0.80 |
Always leave 10-15% buffer so you are not hunting a charger at 0% state of charge.
Why this matters when reading Chinese EV news
Headlines love big numbers. A "700 km electric sedan" sounds unbeatable until you notice the fine print says CLTC. Cross-market shoppers should normalize tests before declaring winners.
Bottom line
Range ratings are compliance tools, not trip planners. EPA, WLTP, and CLTC answer "how do we label this car legally?" - not "how far will I get Friday night in February?" Compare apples to apples, discount for your driving, and trust owner data over press releases.