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Home›Consumption›BMW 840i vs BMW 125d

Consumption comparison

BMW 840i Convertible G15 vs BMW 125d F20LCI: how much do I save per year?

Same car, two powertrains. The simulator below calculates the gap based on your mileage and charging type.

BMWPetrol

840i Convertible G15

68 L · 2021

7,5 L/100km

VS
BMWDieselMost economical

125d F20LCI

52 L · 2018

4,8 L/100km

MotorwayRange & chargingPerformance0-100, top speedConsumptionAnnual TCO

Annual mileage

15 000 km/an

5 000 km50 000 km

Simulated driving mix

Drag anywhere on the bar to adjust

Fuel price

Petrol 95 : 1,99 €/L·Diesel : 1,75 €/L

Annual energy cost · 15 000 km

Typical annual usage : Mix 30% city / 50% road / 20% motorway

BMWPetrol

840i Convertible G15

Annual energy cost · 15 000 km

2 358€

15,72 € / 100 km

Equivalent to 1 185 L of petrol 95 per year

Weighted consumption
7,9 L/100km
Fuel price
1,99 €/L
Fuel used
1185,0 L per year
BMWPetrolMost economical

125d F20LCI

Annual energy cost · 15 000 km

1 289€

8,59 € / 100 km

Equivalent to 648 L of petrol 95 per year

Weighted consumption
4,9 L/100km
Fuel price
1,75 €/L
Fuel used
736,5 L per year
Annual gap 125d vs 840i Convertible+1 069 €/an≈ 537 L petrol 95

BMW 125d F20LCI costs 1 069 €/an less in energy than BMW 840i Convertible G15, over 15 000 km for this driving mix.

≈ 537 L of petrol 95 saved per year

Your savings over the ownership period

Cumulative projection by annual mileage. The cheaper-to-run vehicle widens the gap year after year.

Annual mileage

15 000 km/an

1 year

1 069 €

≈ 537 L petrol 95

3 years

3 208 €

≈ 1612 L petrol 95

5 years

5 346 €

≈ 2687 L petrol 95

10 years

10 693 €

≈ 5373 L petrol 95

Cumulative savings for BMW 125d F20LCI versus BMW 840i Convertible G15. Excluding purchase, insurance, maintenance and depreciation.

Annual fuel cost breakdown

Projection over 15 000 km/year.

BMW

840i Convertible G15

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,157 €/km2 358 €
BMW

125d F20LCI

Fuelkm/year€/kmAnnual cost
Annual fuel1,75 €/L15 000 km0,086 €/km1 289 €

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Frequently asked questions

On a 100 km mixed trip, the BMW 125d is about 45% cheaper than the BMW 840i Convertible with default parameters. This ratio shifts with your actual energy prices - simulate for your profile.

The BMW 125d is cheaper across all distances with default rates. If your energy prices differ significantly, simulate to see the real impact on your budget.