Petrol in Kolkata costs Rs 113.47 per litre and CNG on the Bengal Gas network costs Rs 99.50 per kg (prices as of August 2026). For a typical hatchback that does 18 km/l on petrol and 28 km/kg on CNG, that works out to Rs 6.30 per km on petrol versus Rs 3.55 per km on CNG — a saving of Rs 2.75 every kilometre.
Here is what that difference adds up to every month in Kolkata:
Monthly cost: CNG vs petrol in Kolkata
| Monthly driving | Petrol cost | CNG cost | You save |
|---|---|---|---|
| 1,000 km | Rs 6,304 | Rs 3,554 | Rs 2,750 |
| 1,500 km | Rs 9,456 | Rs 5,330 | Rs 4,125 |
| 2,000 km | Rs 12,608 | Rs 7,107 | Rs 5,501 |
CNG kit payback period in Kolkata
A sequential CNG kit installed in Kolkata typically costs around Rs 65,000. At current Kolkata prices a CNG conversion pays for itself in about 15.8 months if you drive around 1,500 km a month — a strong case for switching. After that, the roughly Rs 4,125 you save every month is pure gain.
Check your own numbers
The calculator below is already loaded with today’s Kolkata prices. Change the driving distance, mileage or kit cost to match your car and see your own payback period.
Prefilled with current Kolkata fuel prices. Adjust any value to match your car.
Frequently Asked Questions
What is the CNG price in Kolkata today?
CNG in Kolkata costs about Rs 99.50 per kg on the Bengal Gas network (as of August 2026). Petrol is about Rs 113.47 per litre.
How much money does CNG save per month in Kolkata?
Driving 1,500 km a month, a CNG hatchback in Kolkata costs about Rs 5,330 in fuel versus Rs 9,456 on petrol — a saving of roughly Rs 4,125 every month.
What is the CNG kit payback period in Kolkata?
With a Rs 65,000 kit and 1,500 km of monthly driving, the payback period in Kolkata is about 15.8 months at current prices.
Is converting to CNG worth it in Kolkata?
Yes — at current prices the kit pays back in about 15.8 months at 1,500 km/month, which is quick.
What is the per-km cost of CNG vs petrol in Kolkata?
About Rs 3.55 per km on CNG versus Rs 6.30 per km on petrol, assuming 28 km/kg and 18 km/l respectively.