What do bed bugs look like

What do bed bugs look like?

You suspect that you might have bed bugs.  You have insect bite marks that are itchy bumps usually three in a row and you have found some dark spots on your bedding.  These are all signs of bed bugs, but the real questions are do I have bed bugs and what do bed bugs look like?  This article will address the later question of what do bed bugs look like.

What do bed bugs look like?  That depends on what stage of their life cycle they are in.

There are six life stages (The egg is not included) five immature (Instar or Nymph) and one adult stage.  Each life stage is completed after a molt; which is the process where they shed their skins also called ecdysis.  Each molted outer shell is a clear, discarded exoskeleton of the bed bugs themselves.

EGGSWhat do bed bugs look like

The first stage in the bed bugs life cycle begins when the female bed bug lays her eggs.  The female will lay up to 5 eggs per day in loose clusters of 10–50 and can produce 200-500 eggs during a lifetime.

The small slightly pear-shaped (cylindrical) pearly-white eggs are 1 mm (1/32 of an inch) long with a ‘lid” like opening at one end through which the young will emerge.  The eggs are sticky allowing them to adhere to surfaces and substrates in their favorite harborages – cracks, crevices and secluded areas.  The tiny eggs are easily overlooked due to their small size and their harborage locations without magnification.


There are 5 Instar (Nymph) stages in the bed bugs evolutionary life cycle from the egg to full adulthood.  The first Instar (Nymphs) hatches in 7-12 days and is about the size of a pinhead, light tan nearly colorless (until they take a blood meal), otherwise resembling the adults, only smaller.  The differences between instar stages is often seen as altered (larger) body proportions, colors, patterns, or changes in the number of body segments.

Each Instar (Nymph) blood meal feeding takes approximately 3-12 minutes at every stage of their lifecycle development.

What do bed bugs look like - 1st instar What do bed bugs look like - 2nd instar What do bed bugs look like - 3rd instar
The 1st Instar can ingest 3-4 times their body weight or 0.34 mg (0.36 ul). The 2nd Instar can ingest 4-5 times their body weight or 0.96 mg (1.01 ul) and are slightly larger than the first Instar. The 3rd Instar can ingest 4-5 times their body weight or 2.08 mg (2.18 ul) and are slightly larger than the second Instar.
What do bed bugs look like - 4th instar What do bed bugs look like - 5th instar
The 4th Instar can ingest 4-5 times their body weight or 4.11 mg (4.32 ul) and are slightly larger than the third Instar. The 5th Instar can ingest 2-6 times their body weight or 7.09 mg (7.44 ul) and are slightly larger than the fourth Instar.

After feeding the young Instar’s (nymph’s) meal is visible through their translucent exoskeleton.  A common reference is that they look like walking poppy seeds.   Each Instar (Nymph) feeds repeatedly, however only one blood meal is needed in order to develop to the next stage in their life cycle.  Keep in mind when doing a bed bug infestation search that it is very difficult to see young Instar’s (Nymph’s) against a fabric or rough surface if they aren’t moving.  The easiest way to detect the Instar (Nymph) bed bugs is by their cast molted exoskeleton skins that accumulate in their harborages.  Instar’s (Nymph’s) can survive for months without feeding, so moving out of an infested area is not likely to have any effect on diminishing their population numbers.


Once the bed bugs reach the Adult stage in their life cycle they have fully matured, molted 5 times and look similar to a large apple seed or about the size of a pencil What do bed bugs look likeeraser.

They are approximately 3/161/4” (6-7 mm) inch long and have developed into a flat, fairly ovoid shaped body, covered with short, golden colored hairs, brown to reddish-brown in color.  They are a wingless insect with a 3 segmented break, 4-segmented antennae, and vestigial wings that feed solely on the blood of animals.  The bed bugs appearance changes dramatically after they’ve fed on a blood meal; their bodies become bloated and dark red from the blood.  Some have described them as “animated blood drops”.

The tips of the male bed bugs abdomen are usually pointed and the female’s abdomen is more rounded.  The male can ingest 1.5 times its body weight or 2.37 mg (2.49 ul) while the female ingests up to 2 times its body weight or 7.81 mg (8.20 ul).  They give off a distinctive musty, sweetish odor, produced by certain chemicals in glands in their ventral thorax.

The female bed bug must feed in order to produce eggs and can lay ~5 eggs a day up to 200-500 eggs during her lifetime, which may be 6-12 months or longer depending on environmental conditions.  An interesting note is that the bed bug can survive for more than a year without feeding!

You should have a pretty good idea on what do bed bugs look like now.  I’m going to change the focus to some of the parts of the bed bug that are important or relevant to this topic.

The bed bugs legs are adapted for crawling and not for climbing smooth surfaces.  There is a claw at the tip which is used for gripping rough surfaces or for gripping their host to insert mouthparts.  Smooth surfaces are the downfall for bed bugs.  That is why bed bug traps with smooth surfaces work so well.  They can crawl in, but once they fall, there is no getting back up or out.

What do bed bugs look like?

Bed bugs are blood sucking insects that feed on humans.  Now that you have answered the question about what do bed bugs look like it is time to investigate the signs of bed bugs and how to get rid of bed bugs yourself.   This is a pest that can be controlled by following some simple guidelines and preventions and knowing what to look for is the first step in controlling bed bugs.