If you’ve just switched to CNG, or you’re planning a trip of around 100 km, this is probably the first question on your mind: How much CNG required for 100 km? It’s a fair question — unlike petrol, where most cars hover in a similar range, CNG consumption swings quite a bit depending on which car you drive, how you drive it, and even the weather in your city.
CNG Required for 100 km Calculator
Select your car’s brand and model to find out exactly how much CNG (in kg) it needs to cover 100 km.
Formula for CNG required for 100 km
There's no complicated math here — just one formula:
CNG required (kg) = Distance (km) ÷ CNG Mileage (km/kg)
So if your car runs at 28 km/kg and you're covering 100 km:
100 ÷ 28 = 3.57 kg
That's it. The only variable that actually matters is your car's mileage — and that's exactly why the same question ("how much CNG for 100 km?") has a different answer for almost every car on the road.
If you want the cost too, just multiply the kg figure by your local CNG price:
3.57 kg × ₹76/kg (example Delhi price) ≈ ₹271 for 100 km
Compare that to a petrol car doing 18 km/l at ₹96/litre — that same 100 km would cost roughly ₹533. This is really the whole reason CNG has become the default choice for anyone driving 40–50+ km a day in India.
Compare CNG vs Petrol vs Diesel running costs of your Car : Click here
How Much CNG Different Cars Need for 100 km
Here's where it gets more specific. CNG mileage isn't uniform — lighter hatchbacks sip far less CNG than SUVs or MPVs carrying more weight. Below are ARAI-certified figures for some of the more common CNG cars sold in India right now.
| Car | ARAI CNG Mileage (km/kg) | CNG Needed for 100 km |
|---|---|---|
| Maruti Suzuki Celerio | 34.13 | 2.93 kg |
| Maruti Suzuki Alto K10 | 33.85 | 2.95 kg |
| Maruti Suzuki WagonR | 33.5 | 2.99 kg |
| Maruti Suzuki S-Presso | 32.73 | 3.06 kg |
| Maruti Suzuki Swift | 32.5 | 3.08 kg |
| Maruti Suzuki Dzire | 31.12 | 3.21 kg |
| Maruti Suzuki Baleno / Toyota Glanza | 30.61 | 3.27 kg |
| Maruti Suzuki Victoris | 28.00 | 3.57 kg |
| Hyundai Aura | 28.4 | 3.52 kg |
| Hyundai Grand i10 Nios | 28.2 | 3.55 kg |
| Hyundai Exter | 27.2 | 3.68 kg |
| Maruti Suzuki Brezza | 25.51 | 3.92 kg |
| Maruti Suzuki Ertiga | 26.11 | 3.83 kg |
| Tata Tiago / Tigor | 26.5 | 3.77 kg |
| Tata Punch | 26.21 | 3.81 kg |
| Tata Altroz | 26.2 | 3.82 kg |
| Maruti Suzuki Eeco | 20.39 | 4.90 kg |
Figures are ARAI-certified (lab-tested) claims current as of 2026 and are meant as a general reference — always check the exact variant of your car, since mileage can shift slightly between trims. A few newer models don't have a confirmed CNG mileage figure yet and are left out of this table rather than guessed.
Why Your Car Real Mileage Might Be Different
Here's something most calculators and articles don't tell you clearly: the ARAI number is a lab figure, tested under controlled conditions with no traffic, no AC, and a specific driving pattern. In real-world Indian city driving, it's common to see 15–25% lower mileage than the claimed figure.
That means if your car is ARAI-rated at 28 km/kg, don't be surprised if you're actually getting closer to 21–24 km/kg in daily Delhi or Mumbai traffic. A few things pull that number down:
- Stop-and-go traffic — CNG engines lose efficiency faster than petrol ones in heavy idling and low-speed crawling, since combustion isn't as clean at low RPMs.
- AC usage — running the AC constantly, especially in summer, can knock off a noticeable chunk of mileage.
- Cold engine starts — most CNG cars run on petrol for the first minute or two after starting until the engine warms up, which slightly affects the average if your trips are short.
- Tyre pressure — under-inflated tyres increase rolling resistance and quietly eat into mileage on any fuel type, CNG included.
- Load and passengers — a fully loaded car with four passengers and luggage will always consume more CNG per km than one person driving alone.
- Driving style — hard acceleration and high cruising speeds burn through CNG noticeably faster than smooth, steady driving.
If you want to know exactly how much CNG your specific car needs for 100 km — not just the claimed average — the most reliable way is to track it yourself: fill up, reset your trip meter, and note how many kg it takes to cover a known distance over a few tanks.
How to Reduce CNG Consumption on Your Daily Commute
A few small habits genuinely make a difference over a month of driving:
- Maintain steady speeds rather than constant acceleration and braking — this matters more for CNG mileage than for petrol.
- Keep tyres at the recommended pressure — check it monthly, not just when it looks low.
- Avoid unnecessary idling — switch off the engine if you're going to be stationary for more than a minute.
- Get your CNG kit serviced on schedule — a poorly tuned system burns more gas for the same output.
- Don't overload the car — clear out extra weight you're not using regularly.
None of these are dramatic changes, but together they can bring your real-world mileage noticeably closer to the ARAI figure.
Frequently Asked Questions
How much CNG does a car need for 100 km?
Most CNG cars in India need between 3 kg and 4 kg of CNG for 100 km. Lighter hatchbacks like the Celerio or WagonR need closer to 3 kg, while heavier SUVs or MPVs like the Brezza or Ertiga need closer to 4 kg.
How do I calculate CNG required for any distance?
Divide your planned distance by your car's CNG mileage in km/kg. For a 300 km trip in a car doing 28 km/kg: 300 ÷ 28 = 10.7 kg of CNG.
Is CNG mileage the same in every city?
The mileage figure itself doesn't change city to city, but the actual kg you use can vary slightly with local temperature, traffic conditions, and altitude. What changes significantly by city is the CNG price per kg, which affects your total cost even if the kg required stays the same.
Why is my car using more CNG than the claimed mileage suggests?
This is completely normal. ARAI figures are lab-tested and don't account for real traffic, AC use, or your specific driving style. A 15–25% gap between claimed and real-world mileage is typical.
How much does 100 km cost on CNG?
It depends on your car's mileage and your local CNG price. As a rough example, a car needing 3.5 kg for 100 km at ₹76/kg would cost around ₹266. Use the calculator above with your own car and local price for an exact figure.
Conclusion
There's no single answer to "How much CNG required for 100 km" that applies to every car — it genuinely depends on what you drive. But as a working range, 3 kg for efficient hatchbacks and up to 4–5 kg for heavier cars and SUVs is a fair estimate to plan around. For your exact car and your local CNG price, the calculator above will do the math instantly — just pick your brand and model.