A turntable platter is the circular rotating platform on which a vinyl record sits during playback. It is one of the main components of a turntable and is responsible for rotating the record smoothly and consistently while the stylus follows its grooves.

The platter is connected to the turntable's drive system, which rotates it at a controlled speed. Most records are played at 33⅓ or 45 revolutions per minute, although some turntables also support 78 rpm records.

Maintaining a stable rotational speed is important because variations in platter speed can affect the pitch and timing of the music. A well-designed turntable therefore aims to keep the platter rotating as consistently as possible.

Turntable platters can be manufactured from materials including aluminium, acrylic, glass and engineered composites. Different materials have different mass, stiffness and resonance characteristics, allowing manufacturers to use the platter as part of the overall mechanical design of the turntable.

The weight of the platter can also be important. A relatively heavy platter has greater rotational inertia, which can help maintain a stable speed once it is rotating. However, platter mass must be considered together with the motor, bearing and overall turntable design.

The platter rotates around a bearing that allows it to turn with minimal friction and unwanted movement. The quality and precision of this bearing can have an important influence on how smoothly and quietly the platter operates.

Many turntables place a separate mat between the platter and the record. Turntable mats can be made from materials such as rubber, felt, cork or leather and provide a surface for the record to rest on while also helping to control vibration.

In a belt-drive turntable, a motor turns the platter using a flexible belt connected either to the platter itself or to a smaller sub-platter underneath it. In a direct-drive turntable, the platter is driven directly by the motor without the use of a belt.

The turntable platter therefore does more than simply provide somewhere to place a record. Together with the motor, bearing and drive system, it provides the stable rotating platform required for the stylus to accurately track the information contained within a vinyl record's grooves.