The rough timeline of events during the putrefaction stage is as follows:
*1–2 days: Pallor mortis, algor mortis, rigor mortis, and livor mortis are the first steps in the process of decomposition before the process of putrefaction.
*2–3 days: Discoloration appears on the skin of the abdomen. The abdomen begins to swell due to gas formation.
*3–4 days: The discoloration spreads and discolored veins become visible.
*5–6 days: The abdomen swells noticeably and the skin blisters.
*10–20 days: Black putrefaction occurs, which is when noxious odors are released from the body and the parts of the body undergo a black discoloration.
*2 weeks: The abdomen is bloated; internal gas pressure nears maximum capacity. 
*3 weeks: Tissues have softened. Organs and cavities are bursting. The nails and hair fall off.
*4 weeks: Soft tissues such as the internal organs begin to liquefy and the face becomes unrecognizable. The skin, muscles, tendons and ligaments degrade exposing the skeleton.
Order of organs' decomposition in the body:
#Larynx and trachea
#Infant brain
#Stomach
#Intestines
#Spleen
#Omentum and mesentery
#Liver
#Adult brain
#Heart
#Lungs
#Kidneys
#Bladder
#Esophagus
#Pancreas
#Diaphragm
#Blood vessels
#Uterus
The rate of putrefaction is greatest in air, followed by water, soil, and earth. The exact rate of putrefaction is dependent upon many factors such as weather, exposure and location. Thus, refrigeration at a morgue or funeral home can retard the process, allowing for burial in three days or so following death without embalming.  The rate increases dramatically in tropical climates. The first external sign of putrefaction in a body lying in air is usually a greenish discoloration of the skin over the region of the cecum, which appears in 12–24 hours. The first internal sign is usually a greenish discoloration on the undersurface of the liver.