How big are Bed Bugs Compared To Other Bugs

In dealing with bed bugs, the first and most important step to take is to identify these insects.

What do bed bugs look like? Bed bugs’ appearance can be tricky sometimes, these insects are tiny and nocturnal so you would hardly notice them. Most often, other bug-like insects have been mistaken for bed bugs. But one way to differentiate bed bugs from these other bugs is their body size. That’s why in this post, we’ll be answering the question of “how big are bed bugs“?.

Generally, an adult bed bug is quite small. The size has often been compared to that of an apple seed which is about 3 to 4 inches or 5 to 7 millimeters long. Bed bugs are long, brown, and flat, but they look like tiny reddish-brown balloons after they feed. Though bed bugs are the size of an apple seed, some bed bugs are smaller and others slightly larger depending on the age and life stages.

How Big Are Bed Bugs?

What bed bugs really look like?

Bed bugs are pretty tiny insects. You would hardly notice them. But to ascertain if the crawling critters you see on your bed are bed bugs, knowing their structure will be of utmost significance.

Bed bugs have a brown tough exoskeleton. They are long, flat-bodied, and have segmented bodies. These segments are in three parts and it includes the antenna which is made up of four parts, short golden hairs, and wing pads that are never used for flying. They can come in different colors depending on their age. Most bed bugs are brown and flat, but they look reddish-brown, balloon-like, and more elongated when they are well-fed.

At this point, it would be easy to mistake this bug for another insect. Bed bug nymphs however are translucent or whitish-yellow. You should know that bed bugs have squat heads and possess six legs with two antennas. They are fast breeders and bloodsuckers. Some people put them in the category of vampires.


Different life stages of bed bugs and their sizes

If you plan to control, get rid of, or become a bed bug expert, their different life stages give you insights into an infestation. For instance, when you notice bed bug eggs, it tells you that you need to disinfect your home. Following the different life stages is a sure step in the right direction. Both insects and animals lay eggs or give birth to continue their life cycle. The life stages of bed bugs include; the egg, the nymph, and the adult bed bug.

How big are bed bug eggs?


Bed bug eggs are usually pearl-white or translucent and look the size of a pinhead. The eggs are quite tiny and hard to spot. When they are about five days old, bed bug eggs are marked by one or more eyespots.

Bed bug eggs are about 1 millimeter in length and can be compared to the size of two grains of salt. These insect eggs are often in clusters with each other. Eggs are laid in cracks and crevices. Places they would hardly be seen. Bed bug eggs take about two weeks to hatch after it’s laid. Bed bugs are quite small insects and so are their eggs.

How big are baby bed bugs?

The size of bed bug nymphs differs in size depending on the growth level and stage. They are smaller than adult bed bugs and their color ranges from whitish-yellow to translucent.

In some of their growth stages, these insects are usually almost invisible and of course very tiny. A newly hatched nymph or baby bed bug is about 1.5 millimeters.

At this stage, the baby bed bug has not developed any tough exoskeleton. It is whitish and would hardly be seen with the naked eye.

Different bed bug nymph stages and their sizes

Usually, bed bug nymphs undergo five molting stages where they shed their exoskeletons to develop tougher and browner skin colors. It takes about 100 days, which is approximately 1 to 2 months for the molting stage to occur before baby bed bugs become full adults. Each molting stage takes not less than ten days to occur. These baby bed bugs will feed on blood as they grow. In fact, they start feeding immediately when they hatch.

First-bed bug nymph stage and size

The first nymph stage could be a day old with 1.5 millimeters in size. It takes about 10 or more days before the newly hatched nymph sheds its exoskeleton. This baby bed bug is whitish in color and somehow translucent.

Second nymph stage

The second nymph stage, with approximately three days to a week old. The size of this baby bed bug is about 2 millimeters. At this stage, the bed bug has begun to develop an exoskeleton. His color fluctuates between brown and white.

Third nymph stage

At the third stage in this growth stage of a baby bed bug, the nymph has grown up to 2.5 millimeters in size. The outer skin layer has begun to look more like the adult bed bug. Though the color is yellow with a little bit of dark brown.

Fourth nymph stage

In the fourth stage of growth and molting, the bed bug nymphs become about 3 millimeters long. It is still quite small at the stage.

Fifth nymph stage

This is the fifth and final molting stage of a baby bed bug. At this stage, the bed bug grows a little longer than the usual pace. It is about 4.5 millimeters long. This bed bug, completing its molting stages is ready to become an adult bed bug. Though it is still yellowish, the bed bug nymph will look almost invisible when it is unfed.

Bed bug nymphs are smaller. Adult nymphs on the other hand are about 5-7 millimeters. When they are unfed, they are about 5 millimeters but when they are well-fed, they grow slightly longer than their unfed size which is around 7 millimeters.

They look round when they feed. Bed bugs often produce a sweet musty smell through glands on the lower side of their bodies. Bed bugs are good at hiding and because they only feed on human and animal blood, you would hardly see them loitering around. But at night, when you are fast asleep, these critters come out in their mass to feed on you until they are full.

How big are bed bugs compared to their lookalikes?

It is no news that there are bugs that we most often mistake for bed bugs. These insects even have similar bites and structures as bed bugs. To identify and know the difference between these insects, you need to be able to differentiate their sizes. Are bed bugs bigger than these bug-like insects or the reverse is the case?

Bed bugs versus fleas

Many people often mistake fleas for bed bugs because of their striking resemblance. They are both reddish-brown and have oval-shaped bodies.

However, these insects are not the same size as bed bugs. Bed bugs are way bigger than fleas. Though fleas are oval-shaped, they are flatter and skinner than bed bugs. With a length of about 1.5 to 3 millimeters.

Technically an adult flea is the size of a bed bug nymph. What differentiates them is that fleas are more oval-shaped and reddish-brown in color. While an adult bed bug is about 5-7 millimeters, an adult flea is 1.5 to 3 millimeters. Bed bugs are definitely bigger than fleas.

Bed bugs versus dust mites

Are bed bugs bigger than mites? To answer this often asked question, I’ll state that mites and bed bugs do not look a lot like each other. In fact, they are mostly found on rodents and other animals. However, when they infest homes, they feed on humans as do bed bugs.

Dust mites are pretty tiny insects and can only really be seen under a microscope. They are less than one-tenth the size of a bed bug. Which is 0.1 to 0.4 millimeters in length. So bed bugs are way bigger than mites.

A typical adult bed bug is the size of an apple seed. You may be wondering since mites would hardly be seen due to their size, how then are they mistaken for bed bugs? Their bites. Mite bites look like bed bug bites.

Bed bugs versus cockroach nymphs

This is another insect species often mistaken for bed bugs. Technically, some would think their nymphs would be bigger than bed bugs because of the size of cockroaches. On the contrary, they are not. Cockroach nymphs are smaller than bed bugs.

They are often whitish or grayish in color. Bed bugs and cockroach nymphs may look alike, but their feeding habit differs.

While cockroach nymphs feed on any food in your house, bed bugs are simply bloodsuckers. They only feed on human and animal blood.

Bed bugs versus bat bugs

Bat bugs are bloodsuckers like bed bugs however, bat bugs feed on the blood of bats. These bugs are oval-shaped like bed bugs and flat.

Even their color is similar. People often mistake bat bugs for bed bugs. The size of a bat bug is within 6 millimeters, about the same range as bed bugs. These insects look like bed bugs in length and size. Only that bed bugs are about 5 millimeters when they have not fed, but will look longer after eating. Bed bugs look a lot like bed bugs.

Bed bugs versus lice

Lice are most often mistaken for bed bugs. Because these insects not only feed on human blood, they feed on parts of your body like your head and can be found in similar places as bed bugs.

Also, people often mistake one for the other as these bugs have similar structures. Lice and bed bugs are both tiny insects and feed on human blood but they differ in size.

Are bed bugs bigger than lice? Yes, bed bugs are bigger than lice. Bed bugs are about a quarter of an inch in length while lice are smaller. In fact, they are tinier than an eighth of an inch.

How big are bed bugs when they start biting?

Bed bugs start feeding shortly after they hatch from their eggs. This is because they need to feed before they begin or undergo their molting stage which is about 10 days after they hatch. Bed bugs are not so big when they start feeding on humans. The smallest bed bug nymph is about 1.5 millimeters long. This is just about the size of a bed bug when it begins to feed on humans or bite humans. They start feeding as newly as they are hatched. Once the food is available, hungry bed bugs will feed to their satisfaction.

How big are bed bugs when they hatch?

Bed bugs are usually half the size of your pinky fingers. But their babies are pretty small when they hatch. A newly hatched bed bug is about 0.5 inches. They are not so big when they hatch and take about five weeks to do so. After which they undergo molting stages before adulthood.


Now that you can comfortably tell the size of bed bugs, controlling them would come easy. Endeavor to take infestation seriously because bed bugs are fast breeders and are good at hiding. Be sure you have been bitten by a bed bug before getting rid of the infestation. See what bed bug bites look like and how to treat them.

There are many ways to get rid of bed bugs but keeping your house clean and tidy might prevent an infestation. Bed bugs have hard exoskeletons and are fast becoming immune to some pesticides. therefore you must know the right repellers and insect killers for them. You can contact bed bug experts for assistance if you cannot handle the infestation on your own.

Leave a comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.