What is the average length of a bed bug?

The average length of a bed bug is typically around 4 to 5 mm when they are not engorged. This size is consistent with their appearance as small, oval-shaped, and reddish-brown insects that feed on the blood of humans and other mammals. Understanding the size of bed bugs is crucial for effective identification and control, as their small size can make them easily overlooked during inspections. Identifying them accurately is key to implementing appropriate pest control measures, as timely and effective action is necessary to curtail infestations. The other sizes presented in the options do not align with the commonly accepted size range for bed bugs, reinforcing that 4 to 5 mm is the correct average length.