MDF is medium-density fiberboard – a building and DIY sheet material commonly used in cabinetry, furniture and molding.

Also due to its non-directional grain structure, MDF is ideal for cutting, machining and drilling without splinters or chipping. The smooth surface makes it a good choice for simple interior design pieces that will be painted, cabinets, shelving, mouldings etc.

Medium-density fibreboard (MDF) is an engineered wood product made by breaking down hardwood or softwood residuals into wood fibres, often in a defibrator, combining it with wax and a resin binder, and forming it into panels by applying high temperature and pressure. MDF is generally more dense than plywood. It is made up of separated fibres, but can be used as a building material similar in application to plywood. It is stronger, and more dense, than particle board.

MDF does not contain knots or rings, making it more uniform than natural woods during cutting and in service.However, MDF is not entirely isotropic, since the fibres are pressed tightly together through the sheet. Typical MDF has a hard, flat, smooth surface that makes it ideal for veneering, as no underlying grain is available to telegraph through the thin veneer as with plywood. A so-called "premium" MDF is available that features more uniform density throughout the thickness of the panel.

MDF is also usable for furniture such as cabinets, because of its strong surface.