The cremation occurs in a 'crematorium' consisting of one or more cremator furnaces or cremation 'retorts' for the ashes. A cremator is an industrial furnace capable of generating temperatures of 870-980 °C (1600-1800 °F) to ensure disintegration of the corpse. A crematorium may be part of chapel or a funeral home, or part of an independent facility or a service offered by a cemetery.

Modern cremator fuels include natural gas and propane. However, coal or coke were used until the early 1960s.

Modern cremators have adjustable control systems that monitor the furnace during cremation.

A cremation furnace is not designed to cremate more than one body at a time, which is illegal in many countries including the USA.

The chamber where the body is placed is called the retort. It is lined with refractory bricks that resist the heat. The bricks are typically replaced every five years due to thermal fatigue.

Modern cremators are computer-controlled to ensure legal and safe use, e.g. the door cannot be opened until the cremator has reached operating temperature. The coffin is inserted (charged) into the retort as quickly as possible to avoid heat loss through the top-opening door. The coffin may be on a charger (motorised trolley) that can quickly insert the coffin, or one that can tilt and tip the coffin into the cremator.

Some crematoria allow relatives to view the charging. This is sometimes done for religious reasons, such as traditional Hindu and Jain funerals.