Automotive & Everyday Calculators

Diesel vs Petrol: How Running Costs Are Actually Calculated

Comparing diesel and petrol running costs isn't just about which fuel is cheaper per liter — it's the combination of price per liter and the vehicle's mileage in that fuel that determines the actual monthly cost, which is why a costlier-per-liter fuel can still work out cheaper to run overall.

How a Car Trip's Fuel Cost Is Calculated

A trip's fuel cost comes from two simple divisions and a multiplication — distance divided by mileage gives the liters needed, and multiplying that by the fuel price gives the total cost.

How a Car's Value Depreciates Over Time

A car's value shrinks by a fixed percentage of whatever it's currently worth each year, not a fixed rupee amount — so the actual rupee loss is largest in the first year and keeps shrinking every year after, even at a constant percentage rate.

How a Road Trip's Total Cost Is Estimated

A road trip's total cost adds fuel cost (distance divided by mileage, times fuel price) to tolls and food/lodging spread across the trip's days — three separate expense categories added together into one figure.

How Car Insurance Premium Is Estimated From IDV and No-Claim Bonus

A car insurance premium estimate starts from the vehicle's Insured Declared Value, applies a base rate to get a starting premium, then reduces that with a No-Claim Bonus discount earned for claim-free years before adding any optional cover — so the same vehicle can carry very different premiums depending on its NCB standing alone.

How Fuel Economy Is Calculated — km/L, MPG, and L/100km

Fuel economy can be expressed three different ways — kilometers per liter, miles per gallon, or liters per 100 kilometers — and two of these three measures run in the opposite direction from the third, which is why comparing fuel economy figures from different sources can be confusing unless you know which measure you're looking at.