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Home›Consumption›BMW 840i vs Porsche Boxster

Consumption comparison

BMW 840i xDrive G15 vs Porsche Boxster 981: how much do I save per year?

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

BMWPetrolMost economical

840i xDrive G15

68 L · 2021

7,8 L/100km

VS
PorschePetrol

Boxster 981

63.973429 L · 2012

10,7 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

BMWPetrolMost economical

840i xDrive G15

Annual energy cost · 15 000 km

2 445€

16,30 € / 100 km

Equivalent to 1 229 L of petrol 95 per year

Weighted consumption
8,2 L/100km
Fuel price
1,99 €/L
Fuel used
1228,5 L per year
PorschePetrol

Boxster 981

Annual energy cost · 15 000 km

3 819€

25,46 € / 100 km

Equivalent to 1 919 L of petrol 95 per year

Weighted consumption
12,8 L/100km
Fuel price
1,99 €/L
Fuel used
1918,8 L per year
Annual gap 840i xDrive vs Boxster+1 374 €/an≈ 690 L petrol 95

BMW 840i xDrive G15 costs 1 374 €/an less in energy than Porsche Boxster 981, over 15 000 km for this driving mix.

≈ 690 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

1 374 €

≈ 690 L petrol 95

3 years

4 121 €

≈ 2071 L petrol 95

5 years

6 869 €

≈ 3452 L petrol 95

10 years

13 738 €

≈ 6903 L petrol 95

Cumulative savings for BMW 840i xDrive G15 versus Porsche Boxster 981. Excluding purchase, insurance, maintenance and depreciation.

Annual fuel cost breakdown

Projection over 15 000 km/year.

BMW

840i xDrive G15

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,163 €/km2 445 €
Porsche

Boxster 981

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,255 €/km3 819 €

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Frequently asked questions

On a 100 km mixed trip, the BMW 840i xDrive is about 35% cheaper than the Porsche Boxster with default parameters. This ratio shifts with your actual energy prices - simulate for your profile.

The BMW 840i xDrive is cheaper across all distances with default rates. If your energy prices differ significantly, simulate to see the real impact on your budget.