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Pololu 4.4:1 Metal Gearmotor 25Dx63L mm MP 12V with 48 CPR Encoder

This gearmotor consists of a medium-power, 12 V brushed DC motor combined with a 4.4:1 metal spur gearbox, and it has an integrated 48 CPR quadrature encoder on the motor shaft, which provides 211.2 counts per revolution of the gearbox’s output shaft. The gearmotor is cylindrical, with a diameter just under 25 mm, and the D-shaped output shaft is 4 mm in diameter and extends 12.5 mm from the face plate of the gearbox. 

Key specifications:

voltage no-load performance stall extrapolation
12 V 1700 RPM, 200 mA

0.8 kg⋅cm (11 oz⋅in), 2.1 A


The diagram below shows the dimensions of the 25D mm line of gearmotors (units are mm over [inches]).

Dimensions of the Pololu 25D mm metal gearmotors with encoders. Units are mm over [inches].


Warning: Do not screw too far into the mounting holes as the screws can hit the gears. We recommend screwing no further than 6 mm (0.24″) into the screw hole.


Size: 25D x 63L mm1
Weight: 95 g
Shaft diameter: 4 mm

General specifications

Gear ratio: 4.4:1
No-load speed @ 12V: 1700 rpm
No-load current @ 12V: 200 mA
Stall current @ 12V: 2100 mA
Stall torque @ 12V: 11 oz·in
No-load speed @ 6V: 850 rpm2
Stall current @ 6V: 1050 mA2
Stall torque @ 6V: 5 oz·in2
Motor type: 2.1A stall @ 12V (MP 12V)
Lead length: 8 in3
Encoders?: Y


1. Length measurement is from gearbox face plate to back of encoder cap (it does not include the output shaft). See dimension diagram for details.
2. This motor will run at 6 V but is intended for operation at 12 V.
3. May vary by a few inches.