Car comparison

BMW 4 Series Gran Coupe (F36) 420ivsBMW 4 Series Convertible (G23) 420i

Compare specs, acceleration, fuel consumption, dimensions, practicality, and estimated running costs side by side.

New comparison

BMW 4 Series Gran Coupe (F36)

420i

184 hp1998 ccGasolineRWDAutomaticTurbochargedCoupe2016-2016

BMW 4 Series Convertible (G23)

420i

184 hp1998 ccGasolineRWDAutomaticTurbochargedCabriolet / convertible2020-2024

Comparison overview

Use the estimates as comparison hints and verify exact figures before making decisions.

BMW 4 Series Gran Coupe (F36) 420i

Quickest 0-100 km/h
7.7 s
Fastest top speed
236 km/h
147 mph
Most powerful
184 hp
137 kW
Lightest
1,540 kg
3,395 lb
Best power-to-weight
119 hp/t
89 kW/t
8.4 kg/hp
Lowest combined fuel consumption
5.8 L/100 km
40.6 mpg US
48.7 mpg UK
Lowest highway consumption
4.7 L/100 km
50.0 mpg US
60.1 mpg UK
Best estimated range
1,034 km
643 mi
Largest trunk
480 L
Best overall score
55/100
Best performance score
49/100
Best economy score
91/100
Best practicality score
68/100

BMW 4 Series Convertible (G23) 420i

Highest torque
300 Nm
221 lb-ft
Lowest city consumption
7.4 L/100 km
31.8 mpg US
38.2 mpg UK

Specification comparison

Specification comparison
Model	BMW4 Series Gran Coupe (F36)420i	BMW4 Series Convertible (G23)420i
Power	184hp137kW	184hp137kW
Torque	270Nm199lb-ft	300Nm221lb-ft
Curb weight	1,540kg3,395lb	1,690kg3,726lb
Gross weight	2,100kg4,630lb	2,185kg4,817lb
Top speed	236 km/h 147 mph	236 km/h 147 mph
To 99% top speed	98.1s99% target: 234 km/h / 145 mph Calculated	107.5s99% target: 234 km/h / 145 mph Calculated
0-100 km/h	7.7s	8.2s
0-200 km/h	33.5s Calculated	36.3s Calculated
0-60 mph	7.3s Calculated	7.8s Calculated
Fuel consumption	5.8L/100 km40.6mpg US48.7mpg UK	6.1L/100 km38.6mpg US46.3mpg UK
Fuel consumption city	7.6L/100 km30.9mpg US37.2mpg UK	7.4L/100 km31.8mpg US38.2mpg UK
Fuel consumption highway	4.7L/100 km50mpg US60.1mpg UK	5.4L/100 km43.6mpg US52.3mpg UK
Quarter mile	15.5s Calculated	15.9s Calculated
Power-to-weight	119hp/t89kW/t54hp/1000 lb Calculated	109hp/t81kW/t49hp/1000 lb Calculated
Torque-to-weight	175Nm/t117lb-ft/ton Calculated	178Nm/t119lb-ft/ton Calculated
Estimated range	1,034km643mi Calculated	967km601mi Calculated
Displacement	1,998cc122cu in	1,998cc122cu in
Length	4,638mm183in	4,768mm188in
Width	1,825mm72in	1,852mm73in
Height	1,389mm55in	1,384mm54in
Wheelbase	2,810mm111in	2,851mm112in
Front track	1,545mm61in	1,575mm62in
Rear track	1,594mm63in	1,611mm63in
Ground clearance	130mm5in	124mm5in
Trunk volume	480L	300L
Max trunk volume	1,300L	385L
Doors	5	2
Seats	5	4
Fuel tank	60L	59L
CO2 emissions	134g/km	-

Performance charts

Use the estimates as comparison hints and verify exact figures before making decisions.

Dyno simulation

Estimated stock-style power and torque curves by engine speed.

BMW 4 Series Gran Coupe (F36) 420iBMW 4 Series Convertible (G23) 420iPowerTorque

Dyno simulation data table
Vehicle	Peak power RPM	Peak torque RPM	Max engine speed
BMW4 Series Gran Coupe (F36)420i	5,000 rpm	1,350-4,600 rpm	5,250 rpm
BMW4 Series Convertible (G23)420i	5,000-6,500 rpm	1,350-4,000 rpm	6,750 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
Metric	BMW4 Series Gran Coupe (F36)420i	BMW4 Series Convertible (G23)420i
	Acceleration checkpoints
0-60 mph 0-97 km/h	7.3 s	7.8 s
0-100 km/h 0-62 mph	7.7 s	8.2 s
0-200 km/h 0-124 mph	33.5 s	36.3 s
Top speed	236 km/h 147 mph	236 km/h 147 mph
	Drag race simulation
60 ft 18 m	2.5 s	2.6 s
330 ft 101 m	6.7 s	6.9 s
1/8 mile 201 m	10.2 s	10.4 s
1000 ft 305 m	13.1 s	13.4 s
1/4 mile 402 m	15.5 s	15.9 s
Trap speed 1/4 mile 402 m	148 km/h 92 mph	145 km/h 90 mph

Power comparison

Bar comparison chart for Power. Higher is better · hp / kW

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	184 hp 137 kW
BMW4 Series Convertible (G23)420i	184 hp 137 kW

Torque comparison

Bar comparison chart for Torque. Higher is better · Nm / lb-ft

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	270 Nm 199 lb-ft
BMW4 Series Convertible (G23)420i	300 Nm 221 lb-ft

Curb weight comparison

Bar comparison chart for Curb weight. Lower is better · kg / lb

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	1,540 kg 3,395 lb
BMW4 Series Convertible (G23)420i	1,690 kg 3,726 lb

Top speed without limiter comparison

Bar comparison chart for Top speed without limiter. Higher is better · km/h / mph

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	236 km/h 147 mph
BMW4 Series Convertible (G23)420i	236 km/h 147 mph

0-100 km/h comparison

Bar comparison chart for 0-100 km/h. Lower is better · seconds

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	7.7 s
BMW4 Series Convertible (G23)420i	8.2 s

The biggest 0-100 km/h difference is between BMW 4 Series Gran Coupe (F36) 420i and BMW 4 Series Convertible (G23) 420i: 0.5 s.

Fuel consumption comparison

Bar comparison chart for Fuel consumption. Lower is better · L/100 km / mpg US / mpg UK

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	5.8 L/100 km 40.6 mpg US 48.7 mpg UK
BMW4 Series Convertible (G23)420i	6.1 L/100 km 38.6 mpg US 46.3 mpg UK

Power-to-weight comparison

Bar comparison chart for Power-to-weight. Higher is better · hp/t / kW/t

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	119 hp/t 89 kW/t 8.4 kg/hp
BMW4 Series Convertible (G23)420i	109 hp/t 81 kW/t 9.2 kg/hp

Estimated range comparison

Bar comparison chart for Estimated range. Higher is better · km / mi

Chart data table
Vehicle	Value
BMW4 Series Gran Coupe (F36)420i	1,034 km 643 mi
BMW4 Series Convertible (G23)420i	967 km 601 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
Vehicle	Power	Acceleration	Top speed
BMW4 Series Gran Coupe (F36)420i	184 hp 137 kW	7.7 s	236 km/h 147 mph
BMW4 Series Convertible (G23)420i	184 hp 137 kW	8.2 s	236 km/h 147 mph

Most attractive quadrant

Scatter chart with performance score on the X axis and practicality score on the Y axis.

Vehicle

Performance score

Practicality score

BMW4 Series Gran Coupe (F36)420i

Power	184 hp 137 kW
0-100 km/h	7.7 s
Top speed 236 km/h 147 mph

Doors/seats	5 doors 5 seats
Trunk	480 L 17.0 cu ft
Length	4,638 mm 182.6 in
Height	1,389 mm 54.7 in

BMW4 Series Convertible (G23)420i

Power	184 hp 137 kW
0-100 km/h	8.2 s
Top speed 236 km/h 147 mph

Doors/seats	2 doors 4 seats
Trunk	300 L 10.6 cu ft
Length	4,768 mm 187.7 in
Height	1,384 mm 54.5 in

Performance vs fuel economy

Cars closer to the top-right corner combine stronger performance with better fuel economy scores.

Vehicle

Performance score

Fuel economy score

BMW4 Series Gran Coupe (F36)420i

Power	184 hp 137 kW
0-100 km/h	7.7 s
Top speed 236 km/h 147 mph

5.8 L/100 km

40.6 mpg US

48.7 mpg UK

BMW4 Series Convertible (G23)420i

Power	184 hp 137 kW
0-100 km/h	8.2 s
Top speed 236 km/h 147 mph

6.1 L/100 km

38.6 mpg US

46.3 mpg UK

BMW 4 Series Gran Coupe (F36) 420i is closest to the top-right balance target for performance and fuel economy.

Acceleration vs fuel consumption

Cars closer to the lower-left corner offer a better mix of quick acceleration and low fuel consumption.

Acceleration vs fuel consumption data table
Vehicle	Fuel consumption, L/100 km	0-100 km/h, s
BMW4 Series Gran Coupe (F36)420i	5.8 L/100 km 40.6 mpg US 48.7 mpg UK	7.7 s
BMW4 Series Convertible (G23)420i	6.1 L/100 km 38.6 mpg US 46.3 mpg UK	8.2 s

Power-to-weight vs fuel consumption

The shaded area favors higher power-to-weight with lower combined fuel consumption.

Power-to-weight vs fuel consumption data table
Vehicle	Power-to-weight, hp/t	Fuel consumption, L/100 km
BMW4 Series Gran Coupe (F36)420i	119 hp/t 89 kW/t 8.4 kg/hp	5.8 L/100 km 40.6 mpg US 48.7 mpg UK
BMW4 Series Convertible (G23)420i	109 hp/t 81 kW/t 9.2 kg/hp	6.1 L/100 km 38.6 mpg US 46.3 mpg UK

Detailed score breakdown

Vehicle

BMW4 Series Gran Coupe (F36)420i

BMW4 Series Convertible (G23)420i

Power

184 hp

137 kW

184 hp

137 kW

Torque

270 Nm

199 lb-ft

300 Nm

221 lb-ft

Acceleration

7.7 s

8.2 s

Top speed

236 km/h

147 mph

236 km/h

147 mph

Lightness

1,540 kg

3,395 lb

1,690 kg

3,726 lb

Fuel consumption

5.8 L/100 km

40.6 mpg US

48.7 mpg UK

6.1 L/100 km

38.6 mpg US

46.3 mpg UK

Practicality

Doors/seats	5 doors 5 seats
Trunk	480 L 17.0 cu ft
Length	4,638 mm 182.6 in
Height	1,389 mm 54.7 in

Doors/seats	2 doors 4 seats
Trunk	300 L 10.6 cu ft
Length	4,768 mm 187.7 in
Height	1,384 mm 54.5 in

Range score

1,034 km

643 mi

967 km

601 mi

CO2 score

134 g/km

Trunk score

480 L

17.0 cu ft

300 L

10.6 cu ft

Power-to-weight score

119 hp/t

89 kW/t

8.4 kg/hp

109 hp/t

81 kW/t

9.2 kg/hp

Overall

Fixed score

Fuel cost and annual usage

Estimate running costs from combined consumption, your annual distance, and the fuel price in your local currency.

Average annual distanceDistance unitFuel price in your local currencyPrice unit

Enter the fuel price in your local currency, for example €/L, $/gal, £/L or any other local currency.

LC = Local Currency

Fuel cost and annual usage
Vehicle	BMW 4 Series Gran Coupe (F36) 420i	BMW 4 Series Convertible (G23) 420i
Consumption	5.8 L/100 km40.6 mpg US48.7 mpg UK	6.1 L/100 km38.6 mpg US46.3 mpg UK
Cost / 100 km	10.15 LC100 km	10.67 LC100 km
Cost / 100 mi	16.33 LC100 mi	17.18 LC100 mi
Annual fuel used	870 L230 US gal191 UK gal	915 L242 US gal201 UK gal
Annual fuel cost	1,523 LC/year	1,601 LC/year