Bed bugs have three life stages and vary in appearance depending on the stage. They start in an egg that is 1mm in length and then are born into 5 baby (also called juvenile or nymph) stages (1.5mm to 4.5mm in length). This is followed by adulthood where the insect grows to approximately 3/8" (5.5mm long).
Bed Bug Actual Size Chart
A picture of bed bug at each stage of development is depicted below.
Pictures are provided to make it easier when asking "how to identify bed
Pictures are also provided to help distinguish bedbugs from other insects which are similar in appearance.
Bed Bug Pictures
What Does a Bed Bug Look Like?
Bed bugs move through 5 instars or stages on their way to adulthood. After hatching they are about the size of a poppy seed. To pass from stage to stage, the need to take in a blood meal. Bed bugs have a stylet on their head which is used to puncture the skin of their human host. Photos and descriptions of each instar can be found below.
Pictures of Bed Bugs at Each Life Stage
In favorable conditions it takes between 4 weeks to 5 weeks to go from a hatched nymph to adult (at 83 to 90 degrees F). A nymph or baby bed bugs can live for 3 to 4 months without a blood meal, adults can live just over a year.
confirming that you have bed bugs
The first signs of an infestation are usually bites on the legs, torso, neck or arms. Since the bites look like the bites of other insects such as mosquitoes, it is important to confirm the presence of the insects in other ways. This includes capturing an identifying an actual insect or the presence of fecal (black or brown marks) on a mattress.
To be sure, the easiest way to confirm that you have an infestation is to have a bed bug expert check a sample bedbug or have them come to your home. Check our list of local bed bug experts here.
Diagram and Anatomy
Diagram of Bedbug
pictures of bed bug eggs
Bedbug eggs are the size of a sesame seed (about 1 mm). They are white and oval shaped. On average, a 3 eggs a day are laid by females (for a total of 200 to 500 per female), which appear glued to the surface. This is why vacuuming is not an effective way to pick up the eggs.
Bed Bug Egg on Surface
baby bed bugs
Nymphs are lite brown and are approximately 5/100 of an inch in length. These baby bed bugs will change in appearance before and after feeding. They need to feed in order to move from instar to instar.
Bed Bug Before Feeding on Host
Bed Bug After Feeding
Bed Bug Adults
Bed Bug Size Change After Feeding
Adult bed bugs are approximately 3/16 of an inch long. When you identify bed bugs, check the color which is red/brown in color and look for a 3 segment beak and 4 segment antennae. They have wings, which are referred to as being vestigial, meaning that they aren't used. The bugs are covered by fine gold colored hair.
Dorsal (Head) View of Bed Bug
The bed bugs give off an odor that can be detected by dogs, which is why many bed bug pest control companies use dogs to identify places where bed bugs are hiding.
Adult Male Bed Bug
Adult Female Bed Bug
From a side view bedbugs are flat.
Bed Bug - Side View
A bed bug changes in appearance and size before and after feeding as shown below: A bed bug feeds every few days, with feeding itself taking about 10 minutes.
Bed Bug Before and After Feeding
Insects That Look Like Bedbugs
There are several insects that look like bed bugs. If you aren't sure, send a picture or insect to the Cornell Diagnostic Laboratory for review ($25 charge).
similar in appearance to bed bugs are shown below:
Bed Bug Compared to a Bat Bug
Look for Young Roaches that look like bed bugs. They lay rectangular egg cases and fecal pellets. The color is more
brown than red.
Carpet Beetle and Warehouse Beetle
Carpet and Warehouse beetles may appear in beds feeding
on hair and feathers. Larvae may shed tiny hairs that cause skin itch. These insects do not bite people.
Shiny Spider Beetles
Shiny spider beetles are often confused with bed bugs and ticks. They feed on dried plant material, seeds, or dried meat and do not bite humans.
insects that bite
Each of these free brochures provides additional information on insects that bite.
Questions and answers
Ask a Question or Share Your Bed Bug Experience With Others
Do you have a question or great story about bed bugs? Share it!
What Other Visitors Have Said About Bed Bugs
Click below to see contributions from other visitors to this page...
Is this a bed bug? Not rated yet
Is this a bedbug???? Editor Comment: Hi Angela, It looks more like a beetle than a bedbug. To be certain we suggest sending the photo or the actual …
Strange Bug! Not rated yet
Hello! I'm wondering if you can please help me identify this bug. I live in Back Bay Boston and found it on my duvet cover on my bed one morning. I sent …
I need help badly Not rated yet
I found 4 small bedbug nymph looking things on a vinyl sofa in a bedroom in my very old home. The sofa is right near a chimney where birds are currently …