Diesel vs Petrol Cost Calculator
Compare the monthly and annual fuel cost of a diesel vehicle against a petrol vehicle for your driving distance.
- Free to use
- Accurate results
- No registration required
- Works on all devices
Your result
₹3,250
Monthly savings with diesel
AI explanation
Formula
Fuel cost = (distance ÷ km per liter) × price per liter, computed separately for diesel and petrolWorked example
1,500 km/month, diesel ₹90/l at 20 km/l vs petrol ₹100/l at 15 km/l
| Field | Value |
|---|---|
| Monthly driving distance | 1500 |
| Diesel price (per liter) | 90 |
| Diesel vehicle mileage (km/l) | 20 |
| Petrol price (per liter) | 100 |
| Petrol vehicle mileage (km/l) | 15 |
| Diesel monthly fuel cost | 6750 |
| Petrol monthly fuel cost | 10000 |
| Monthly savings with diesel | 3250 |
Assumptions
- Compares only fuel cost — excludes the typically higher upfront price of diesel vehicles, and any maintenance cost differences between diesel and petrol engines.
- A positive savings figure means diesel is cheaper to run per month at your entered distance and rates; a negative figure means petrol is cheaper.
Frequently asked questions
Is diesel always cheaper to run than petrol?
Not always — it depends on the price gap between diesel and petrol in your area, and how much better mileage your specific diesel vehicle gets. This calculator uses your actual numbers rather than a general rule of thumb.
Does this include the higher purchase price of diesel vehicles?
No — diesel vehicles and their spare parts are often more expensive upfront and to maintain. Factor that difference in separately when deciding, especially for lower annual driving distances where fuel savings take longer to offset it.
How much driving makes diesel worth it?
Generally, diesel becomes more cost-effective at higher annual driving distances, since the per-km fuel savings need enough distance to offset the higher purchase price — there's no universal threshold, since it depends on your specific price and mileage figures.