Car comparison

BMW 4 Series Convertible (G23) M440dvsBMW X6 (G06 LCI) · Facelift 2023 40d

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

New comparison

BMW 4 Series Convertible (G23)

M440d

340 hp2993 ccDieselAWDAutomaticTurbochargedCabriolet / convertible2021-2024

BMW X6 (G06 LCI) · Facelift 2023

40d

340 hp2993 ccDieselAWDAutomaticTurbocharged2023-present

Comparison overview

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

BMW 4 Series Convertible (G23) M440d

Quickest 0-100 km/h
5.0 s
Fastest top speed
260 km/h
162 mph Unrestricted
250 km/h
155 mph Restricted
Most powerful
340 hp
254 kW
Highest torque
700 Nm
516 lb-ft
Lightest
1,980 kg
4,365 lb
Best power-to-weight
172 hp/t
128 kW/t
5.8 kg/hp
Lowest combined fuel consumption
6.6 L/100 km
35.6 mpg US
42.8 mpg UK
Best performance score
74/100
Best economy score
89/100

BMW X6 (G06 LCI) Facelift 2023 40d

Best estimated range
976 km
606 mi
Largest trunk
580 L
Best overall score
72/100
Best practicality score
79/100

Specification comparison

Specification comparison
Model	BMW4 Series Convertible (G23)M440d	BMWX6 (G06 LCI)Facelift 202340d
Power	340hp254kW	340hp254kW
Torque	700Nm516lb-ft	700Nm516lb-ft
Curb weight	1,980kg4,365lb	2,245kg4,949lb
Gross weight	2,480kg5,467lb	2,985kg6,581lb
Top speed	Unrestricted 260 km/h162 mph Restricted 250 km/h155 mph Calculated	245 km/h 152 mph
To 99% top speed	70.3s99% target: 257 km/h / 160 mph Calculated	91.0s99% target: 243 km/h / 151 mph Calculated
0-100 km/h	5.0s	5.5s
0-200 km/h	18.3s Calculated	25.0s Calculated
0-60 mph	4.7s Calculated	5.2s Calculated
Fuel consumption	6.6L/100 km35.6mpg US42.8mpg UK	8.2L/100 km28.7mpg US34.4mpg UK
Quarter mile	13.2s Calculated	13.8s Calculated
Power-to-weight	172hp/t128kW/t78hp/1000 lb Calculated	151hp/t113kW/t69hp/1000 lb Calculated
Torque-to-weight	354Nm/t237lb-ft/ton Calculated	312Nm/t209lb-ft/ton Calculated
Estimated range	894km555mi Calculated	976km606mi Calculated
Displacement	2,993cc183cu in	2,993cc183cu in
Length	4,768mm188in	4,960mm195in
Width	1,852mm73in	2,004mm79in
Height	1,384mm54in	1,700mm67in
Wheelbase	2,851mm112in	2,975mm117in
Front track	1,573mm62in	1,678mm66in
Rear track	1,612mm63in	1,698mm67in
Ground clearance	-	216mm9in
Trunk volume	300L	580L
Max trunk volume	385L	1,530L
Doors	2	5
Seats	4	5
Fuel tank	59L	80L

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 Convertible (G23) M440dBMW X6 (G06 LCI) Facelift 2023 40dPowerTorque

Dyno simulation data table
Vehicle	Peak power RPM	Peak torque RPM	Max engine speed
BMW4 Series Convertible (G23)M440d	4,400 rpm	1,750-2,250 rpm	4,650 rpm
BMWX6 (G06 LCI)Facelift 202340d	4,400 rpm	1,750-2,250 rpm	4,650 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
Metric	BMW4 Series Convertible (G23)M440d	BMWX6 (G06 LCI)Facelift 202340d
	Acceleration checkpoints
0-60 mph 0-97 km/h	4.7 s	5.2 s
0-100 km/h 0-62 mph	5.0 s	5.5 s
0-200 km/h 0-124 mph	18.3 s	25.0 s
Top speed	Unrestricted 260 km/h162 mph Restricted 250 km/h155 mph Limited	245 km/h 152 mph
	Drag race simulation
60 ft 18 m	2.1 s	2.1 s
330 ft 101 m	5.7 s	5.8 s
1/8 mile 201 m	8.6 s	8.9 s
1000 ft 305 m	11.1 s	11.5 s
1/4 mile 402 m	13.2 s	13.8 s
Trap speed 1/4 mile 402 m	174 km/h 108 mph	161 km/h 100 mph

Power comparison

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

Chart data table
Vehicle	Value
BMW4 Series Convertible (G23)M440d	340 hp 254 kW
BMWX6 (G06 LCI)Facelift 202340d	340 hp 254 kW

Torque comparison

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

Chart data table
Vehicle	Value
BMW4 Series Convertible (G23)M440d	700 Nm 516 lb-ft
BMWX6 (G06 LCI)Facelift 202340d	700 Nm 516 lb-ft

Curb weight comparison

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

Chart data table
Vehicle	Value
BMW4 Series Convertible (G23)M440d	1,980 kg 4,365 lb
BMWX6 (G06 LCI)Facelift 202340d	2,245 kg 4,949 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 Convertible (G23)M440d	Unrestricted 260 km/h162 mph Restricted 250 km/h155 mph
BMWX6 (G06 LCI)Facelift 202340d	245 km/h 152 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 Convertible (G23)M440d	5.0 s
BMWX6 (G06 LCI)Facelift 202340d	5.5 s

The biggest 0-100 km/h difference is between BMW 4 Series Convertible (G23) M440d and BMW X6 (G06 LCI) Facelift 2023 40d: 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 Convertible (G23)M440d	6.6 L/100 km 35.6 mpg US 42.8 mpg UK
BMWX6 (G06 LCI)Facelift 202340d	8.2 L/100 km 28.7 mpg US 34.4 mpg UK

The biggest fuel consumption difference is between BMW 4 Series Convertible (G23) M440d and BMW X6 (G06 LCI) Facelift 2023 40d: 1.6 L/100 km.

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 Convertible (G23)M440d	172 hp/t 128 kW/t 5.8 kg/hp
BMWX6 (G06 LCI)Facelift 202340d	151 hp/t 113 kW/t 6.6 kg/hp

Estimated range comparison

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

Chart data table
Vehicle	Value
BMW4 Series Convertible (G23)M440d	894 km 555 mi
BMWX6 (G06 LCI)Facelift 202340d	976 km 606 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
Vehicle	Power	Acceleration	Top speed
BMW4 Series Convertible (G23)M440d	340 hp 254 kW	5.0 s	Unrestricted 260 km/h162 mph Restricted 250 km/h155 mph
BMWX6 (G06 LCI)Facelift 202340d	340 hp 254 kW	5.5 s	245 km/h 152 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 Convertible (G23)M440d

Power	340 hp 254 kW
0-100 km/h	5.0 s
Top speed Unrestricted 260 km/h162 mph Restricted 250 km/h155 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

BMWX6 (G06 LCI)Facelift 202340d

Power	340 hp 254 kW
0-100 km/h	5.5 s
Top speed 245 km/h 152 mph

Doors/seats	5 doors 5 seats
Trunk	580 L 20.5 cu ft
Length	4,960 mm 195.3 in
Height	1,700 mm 66.9 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 Convertible (G23)M440d

Power	340 hp 254 kW
0-100 km/h	5.0 s
Top speed Unrestricted 260 km/h162 mph Restricted 250 km/h155 mph

6.6 L/100 km

35.6 mpg US

42.8 mpg UK

BMWX6 (G06 LCI)Facelift 202340d

Power	340 hp 254 kW
0-100 km/h	5.5 s
Top speed 245 km/h 152 mph

8.2 L/100 km

28.7 mpg US

34.4 mpg UK

BMW 4 Series Convertible (G23) M440d 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 Convertible (G23)M440d	6.6 L/100 km 35.6 mpg US 42.8 mpg UK	5.0 s
BMWX6 (G06 LCI)Facelift 202340d	8.2 L/100 km 28.7 mpg US 34.4 mpg UK	5.5 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 Convertible (G23)M440d	172 hp/t 128 kW/t 5.8 kg/hp	6.6 L/100 km 35.6 mpg US 42.8 mpg UK
BMWX6 (G06 LCI)Facelift 202340d	151 hp/t 113 kW/t 6.6 kg/hp	8.2 L/100 km 28.7 mpg US 34.4 mpg UK

Detailed score breakdown

Vehicle

BMW4 Series Convertible (G23)M440d

BMWX6 (G06 LCI)Facelift 202340d

Power

340 hp

254 kW

340 hp

254 kW

Torque

700 Nm

516 lb-ft

700 Nm

516 lb-ft

Acceleration

5.0 s

5.5 s

Top speed

Unrestricted

260 km/h162 mph

Restricted

250 km/h155 mph

245 km/h

152 mph

Lightness

1,980 kg

4,365 lb

2,245 kg

4,949 lb

Fuel consumption

6.6 L/100 km

35.6 mpg US

42.8 mpg UK

8.2 L/100 km

28.7 mpg US

34.4 mpg UK

Practicality

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

Doors/seats	5 doors 5 seats
Trunk	580 L 20.5 cu ft
Length	4,960 mm 195.3 in
Height	1,700 mm 66.9 in

Range score

894 km

555 mi

976 km

606 mi

Trunk score

300 L

10.6 cu ft

580 L

20.5 cu ft

Power-to-weight score

172 hp/t

128 kW/t

5.8 kg/hp

151 hp/t

113 kW/t

6.6 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 Convertible (G23) M440d	BMW X6 (G06 LCI) Facelift 2023 40d
Consumption	6.6 L/100 km35.6 mpg US42.8 mpg UK	8.2 L/100 km28.7 mpg US34.4 mpg UK
Cost / 100 km	11.55 LC100 km	14.35 LC100 km
Cost / 100 mi	18.59 LC100 mi	23.09 LC100 mi
Annual fuel used	990 L262 US gal218 UK gal	1,230 L325 US gal271 UK gal
Annual fuel cost	1,733 LC/year	2,153 LC/year