Car comparison

BMW 1 Series Convertible (E88) 125ivsBMW 4 Series Convertible (F33) 420d

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

New comparison

BMW 1 Series Convertible (E88)

125i

218 hp2996 ccGasolineRWDManualNaturally aspiratedCabriolet / convertible2008-2011
VS

BMW 4 Series Convertible (F33)

420d

184 hp1995 ccDieselRWDManualTurbochargedCabriolet / convertible2014-2015

Comparison overview

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

Best choices

BMW 1 Series Convertible (E88) 125i

  • Quickest 0-100 km/h
    6.8 s
  • Fastest top speed
    238 km/h
    148 mph
  • Most powerful
    218 hp
    163 kW
  • Lightest
    1,510 kg
    3,329 lb
  • Best power-to-weight
    144 hp/t
    108 kW/t
    6.9 kg/hp
  • Largest trunk
    260 L
  • Best overall score
    50/100
  • Best performance score
    53/100
  • Best practicality score
    43/100

BMW 4 Series Convertible (F33) 420d

  • Highest torque
    380 Nm
    280 lb-ft
  • Lowest combined fuel consumption
    5.1 L/100 km
    46.1 mpg US
    55.4 mpg UK
  • Lowest city consumption
    6.0 L/100 km
    39.2 mpg US
    47.1 mpg UK
  • Lowest highway consumption
    4.5 L/100 km
    52.3 mpg US
    62.8 mpg UK
  • Lowest CO2 emissions
    133 g/km
  • Best estimated range
    1,118 km
    694 mi
  • Best economy score
    93/100

Specification comparison

Specification comparison
ModelBMW1 Series Convertible (E88)125iBMW4 Series Convertible (F33)420d
Power
218hp163kW
184hp137kW
Torque
270Nm199lb-ft
380Nm280lb-ft
Curb weight
1,510kg3,329lb
1,680kg3,704lb
Gross weight
1,950kg4,299lb
2,150kg4,740lb
Top speed
238 km/h
148 mph
235 km/h
146 mph
To 99% top speed
88.5s99% target: 236 km/h / 146 mph
Calculated
105.9s99% target: 233 km/h / 145 mph
Calculated
0-100 km/h
6.8s
8.2s
0-200 km/h
29.3s
Calculated
36.5s
Calculated
0-60 mph
6.4s
Calculated
7.8s
Calculated
Fuel consumption
8.1L/100 km29mpg US34.9mpg UK
5.1L/100 km46.1mpg US55.4mpg UK
Fuel consumption city
11.7L/100 km20.1mpg US24.1mpg UK
6L/100 km39.2mpg US47.1mpg UK
Fuel consumption highway
6L/100 km39.2mpg US47.1mpg UK
4.5L/100 km52.3mpg US62.8mpg UK
Quarter mile
14.8s
Calculated
15.9s
Calculated
Power-to-weight
144hp/t108kW/t65hp/1000 lb
Calculated
110hp/t82kW/t50hp/1000 lb
Calculated
Torque-to-weight
179Nm/t120lb-ft/ton
Calculated
226Nm/t151lb-ft/ton
Calculated
Estimated range
654km407mi
Calculated
1,118km694mi
Calculated
Displacement
2,996cc183cu in
1,995cc122cu in
Length
4,360mm172in
4,638mm183in
Width
1,748mm69in
1,825mm72in
Height
1,411mm56in
1,384mm54in
Wheelbase
2,660mm105in
2,810mm111in
Front track
1,474mm58in
1,545mm61in
Rear track
1,507mm59in
1,594mm63in
Ground clearance
140mm6in
130mm5in
Trunk volume
260L
220L
Max trunk volume
305L
370L
Doors
2
2
Seats
4
4
Fuel tank
53L
57L
CO2 emissions
195g/km
133g/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 1 Series Convertible (E88) 125iBMW 4 Series Convertible (F33) 420dPowerTorque
  • BMW 1 Series Convertible (E88) 125i: Power / Torque
  • BMW 4 Series Convertible (F33) 420d: Power / Torque
Dyno simulation data table
VehiclePeak power RPMPeak torque RPMMax engine speed
BMW1 Series Convertible (E88)125i6,100 rpm2,500-4,250 rpm6,350 rpm
BMW4 Series Convertible (F33)420d4,000 rpm1,750-2,750 rpm4,250 rpm

Acceleration curve

Estimated speed over time for selected vehicles.

Acceleration and drag-race table
MetricBMW1 Series Convertible (E88)125iBMW4 Series Convertible (F33)420d
Acceleration checkpoints
0-60 mph
0-97 km/h
6.4 s
7.8 s
0-100 km/h
0-62 mph
6.8 s
8.2 s
0-200 km/h
0-124 mph
29.3 s
36.5 s
Top speed
238 km/h
148 mph
235 km/h
146 mph
Drag race simulation
60 ft
18 m
2.4 s
2.6 s
330 ft
101 m
6.4 s
6.9 s
1/8 mile
201 m
9.7 s
10.4 s
1000 ft
305 m
12.5 s
13.4 s
1/4 mile
402 m
14.8 s
15.9 s
Trap speed
1/4 mile
402 m
154 km/h
96 mph
145 km/h
90 mph

Power comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i
218 hp
163 kW
BMW4 Series Convertible (F33)420d
184 hp
137 kW

BMW 1 Series Convertible (E88) 125i has 34 hp more than BMW 4 Series Convertible (F33) 420d.

The biggest power difference is between BMW 4 Series Convertible (F33) 420d and BMW 1 Series Convertible (E88) 125i: 34 hp (25 kW).

Torque comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i
270 Nm
199 lb-ft
BMW4 Series Convertible (F33)420d
380 Nm
280 lb-ft

Curb weight comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i
1,510 kg
3,329 lb
BMW4 Series Convertible (F33)420d
1,680 kg
3,704 lb

Top speed without limiter comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i
238 km/h
148 mph
BMW4 Series Convertible (F33)420d
235 km/h
146 mph

0-100 km/h comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i6.8 s
BMW4 Series Convertible (F33)420d8.2 s

The biggest 0-100 km/h difference is between BMW 1 Series Convertible (E88) 125i and BMW 4 Series Convertible (F33) 420d: 1.4 s.

Fuel consumption comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i
8.1 L/100 km
29.0 mpg US
34.9 mpg UK
BMW4 Series Convertible (F33)420d
5.1 L/100 km
46.1 mpg US
55.4 mpg UK

The biggest fuel consumption difference is between BMW 4 Series Convertible (F33) 420d and BMW 1 Series Convertible (E88) 125i: 3.0 L/100 km.

Power-to-weight comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i
144 hp/t
108 kW/t
6.9 kg/hp
BMW4 Series Convertible (F33)420d
110 hp/t
82 kW/t
9.1 kg/hp

Estimated range comparison

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

Chart data table
VehicleValue
BMW1 Series Convertible (E88)125i
654 km
407 mi
BMW4 Series Convertible (F33)420d
1,118 km
694 mi

Performance spider chart

Radar chart comparing normalized performance and fuel-consumption scores.

Chart data table
VehiclePowerAccelerationTop speed
BMW1 Series Convertible (E88)125i
218 hp
163 kW
6.8 s
238 km/h
148 mph
BMW4 Series Convertible (F33)420d
184 hp
137 kW
8.2 s
235 km/h
146 mph

Most attractive quadrant

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

Chart data table
VehiclePerformance scorePracticality score
BMW1 Series Convertible (E88)125i
Power
218 hp
163 kW
0-100 km/h6.8 s
Top speed
238 km/h
148 mph
Doors/seats
2 doors
4 seats
Trunk
260 L
9.2 cu ft
Length
4,360 mm
171.7 in
Height
1,411 mm
55.6 in
BMW4 Series Convertible (F33)420d
Power
184 hp
137 kW
0-100 km/h8.2 s
Top speed
235 km/h
146 mph
Doors/seats
2 doors
4 seats
Trunk
220 L
7.8 cu ft
Length
4,638 mm
182.6 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.

Performance vs fuel economy data table
VehiclePerformance scoreFuel economy score
BMW1 Series Convertible (E88)125i
Power
218 hp
163 kW
0-100 km/h6.8 s
Top speed
238 km/h
148 mph
8.1 L/100 km
29.0 mpg US
34.9 mpg UK
BMW4 Series Convertible (F33)420d
Power
184 hp
137 kW
0-100 km/h8.2 s
Top speed
235 km/h
146 mph
5.1 L/100 km
46.1 mpg US
55.4 mpg UK

BMW 1 Series Convertible (E88) 125i 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
VehicleFuel consumption, L/100 km0-100 km/h, s
BMW1 Series Convertible (E88)125i
8.1 L/100 km
29.0 mpg US
34.9 mpg UK
6.8 s
BMW4 Series Convertible (F33)420d
5.1 L/100 km
46.1 mpg US
55.4 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
VehiclePower-to-weight, hp/tFuel consumption, L/100 km
BMW1 Series Convertible (E88)125i
144 hp/t
108 kW/t
6.9 kg/hp
8.1 L/100 km
29.0 mpg US
34.9 mpg UK
BMW4 Series Convertible (F33)420d
110 hp/t
82 kW/t
9.1 kg/hp
5.1 L/100 km
46.1 mpg US
55.4 mpg UK

Detailed score breakdown

Detailed score breakdown
VehicleBMW1 Series Convertible (E88)125iBMW4 Series Convertible (F33)420d
Power
218 hp
163 kW
184 hp
137 kW
Torque
270 Nm
199 lb-ft
380 Nm
280 lb-ft
Acceleration
6.8 s
8.2 s
Top speed
238 km/h
148 mph
235 km/h
146 mph
Lightness
1,510 kg
3,329 lb
1,680 kg
3,704 lb
Fuel consumption
8.1 L/100 km
29.0 mpg US
34.9 mpg UK
5.1 L/100 km
46.1 mpg US
55.4 mpg UK
Practicality
Doors/seats
2 doors
4 seats
Trunk
260 L
9.2 cu ft
Length
4,360 mm
171.7 in
Height
1,411 mm
55.6 in
Doors/seats
2 doors
4 seats
Trunk
220 L
7.8 cu ft
Length
4,638 mm
182.6 in
Height
1,384 mm
54.5 in
Range score
654 km
407 mi
1,118 km
694 mi
CO2 score
195 g/km
133 g/km
Trunk score
260 L
9.2 cu ft
220 L
7.8 cu ft
Power-to-weight score
144 hp/t
108 kW/t
6.9 kg/hp
110 hp/t
82 kW/t
9.1 kg/hp
Overall
Fixed score
Fixed score

Fuel cost and annual usage

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

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
VehicleBMW 1 Series Convertible (E88) 125iBMW 4 Series Convertible (F33) 420d
Consumption8.1 L/100 km29 mpg US34.9 mpg UK5.1 L/100 km46.1 mpg US55.4 mpg UK
Cost / 100 km14.17 LC100 km8.92 LC100 km
Cost / 100 mi22.81 LC100 mi14.36 LC100 mi
Annual fuel used1,215 L321 US gal267 UK gal765 L202 US gal168 UK gal
Annual fuel cost2,126 LC/year1,339 LC/year

Head-to-head comparisons

BMW 1 Series Convertible (E88) 125i

  • Has 34 hp more
  • Is 170 kg lighter
  • Is 1.4 s quicker from 0-100 km/h
  • Has 3 km/h (2 mph) higher top speed
  • Has 35 hp/t better power-to-weight
  • Has 40 L more trunk volume

Pros

  • Quickest 0-100 km/h in this comparison
  • Highest top speed
  • Most powerful
  • Lightest
  • Best power-to-weight ratio
  • Largest trunk

Cons

  • Highest combined fuel consumption
  • Highest CO2 emissions

BMW 4 Series Convertible (F33) 420d

  • Has 110 Nm more
  • Uses 3.0 L/100 km less fuel
  • Has 463 km (288 mi) more estimated range
  • Emits 62 g/km less CO2

Pros

  • Highest torque
  • Lowest combined fuel consumption
  • Best estimated range

Cons

  • Slowest 0-100 km/h
  • Lowest power
  • Heaviest
  • Lowest top speed
  • Smallest trunk

Choose cars to compare

Brand
Model
Generation
Engine or modification
BMW 1 Series Convertible (E88) 125i
BMW 4 Series Convertible (F33) 420d
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