ARAI Mileage vs Real-World Mileage: Why the Numbers Never Match
How ARAI actually tests fuel efficiency, why your car delivers 20-30% less, and how to read the sticker figure correctly before you buy.
Every car sold in India carries an ARAI-certified fuel efficiency figure. Almost nobody achieves it. That is not a scandal — it is a consequence of how the test is designed.
How ARAI actually measures mileage
The car never touches a road. It sits on a chassis dynamometer in a climate-controlled lab and follows the Modified Indian Driving Cycle (MIDC), part of the Bharat Stage emission test procedure. The economy figure is derived from the carbon balance of the exhaust gases, not from a fuel flow meter.
The test conditions
- Ambient temperature held between 20°C and 30°C
- Air conditioning switched off
- No passengers or luggage beyond a fixed reference mass
- Average speed of roughly 34 km/h with a top speed of 90 km/h
- No gradients, no headwind, no potholes, no traffic
Why your number is lower
| Factor | Typical penalty |
|---|---|
| Air conditioning in Indian summer | 8-15% |
| Stop-go city traffic | 10-20% |
| Four passengers plus luggage | 3-6% |
| Under-inflated tyres | 2-3% |
| Aggressive acceleration | 10-20% |
Stack these and a 24 km/l ARAI hatchback comfortably lands at 16-18 km/l in Mumbai traffic. That is not a defective car.
The rule of thumb
For planning purposes, assume you will see:
- Petrol: 70-75% of ARAI in the city, 85-90% on the highway
- Diesel: 78-85% of ARAI — diesels degrade less in traffic
- CNG: 78-85% of the ARAI km/kg figure
- Strong hybrid: 80-88% — hybrids are closest to their claim because the test cycle's low speeds suit them
Why hybrids look so good
The MIDC's low average speed lets a strong hybrid run on electric power for a large share of the cycle. That flatters the number — but unlike most flattery, it partly holds up in the real world, because Indian city traffic is also slow. This is why the Grand Vitara and Hyryder hybrids genuinely return 22-24 km/l for owners.
What we publish instead
Every car page on MyCarMileage lists the ARAI figure and a real-world figure derived from owner-submitted fill-up logs. Read our methodology for how we clean and aggregate that data, and submit your own to improve it.
Put this into practice
Measure what your car actually returns, then see what it costs you every month.