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Home›Consumption›Porsche 911 vs BMW 420d

Consumption comparison

Porsche 911 Carrera GTS Cabriolet 991.2 vs BMW 420d Convertible G22: how much do I save per year?

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

PorschePetrol

911 Carrera GTS Cabriolet 991.2

63.973429 L · 2018

11,2 L/100km

VS
BMWDieselMost economical

420d Convertible G22

59 L · 2021

4,5 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

PorschePetrol

911 Carrera GTS Cabriolet 991.2

Annual energy cost · 15 000 km

3 382€

22,55 € / 100 km

Equivalent to 1 700 L of petrol 95 per year

Weighted consumption
11,3 L/100km
Fuel price
1,99 €/L
Fuel used
1699,5 L per year
BMWPetrolMost economical

420d Convertible G22

Annual energy cost · 15 000 km

1 210€

8,07 € / 100 km

Equivalent to 608 L of petrol 95 per year

Weighted consumption
4,6 L/100km
Fuel price
1,75 €/L
Fuel used
691,5 L per year
Annual gap 420d Convertible vs 911 Carrera GTS Cabriolet+2 172 €/an≈ 1091 L petrol 95

BMW 420d Convertible G22 costs 2 172 €/an less in energy than Porsche 911 Carrera GTS Cabriolet 991.2, over 15 000 km for this driving mix.

≈ 1091 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

2 172 €

≈ 1091 L petrol 95

3 years

6 516 €

≈ 3274 L petrol 95

5 years

10 859 €

≈ 5457 L petrol 95

10 years

21 719 €

≈ 10914 L petrol 95

Cumulative savings for BMW 420d Convertible G22 versus Porsche 911 Carrera GTS Cabriolet 991.2. Excluding purchase, insurance, maintenance and depreciation.

Annual fuel cost breakdown

Projection over 15 000 km/year.

Porsche

911 Carrera GTS Cabriolet 991.2

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,225 €/km3 382 €
BMW

420d Convertible G22

Fuelkm/year€/kmAnnual cost
Annual fuel1,75 €/L15 000 km0,081 €/km1 210 €

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Frequently asked questions

On a 100 km mixed trip, the BMW 420d Convertible is about 65% cheaper than the Porsche 911 Carrera GTS Cabriolet with default parameters. This ratio shifts with your actual energy prices — simulate for your profile.

The BMW 420d Convertible is cheaper across all distances with default rates. If your energy prices differ significantly, simulate to see the real impact on your budget.