Bed bugs, unfortunately, are among the most common household pests, meaning getting rid of them can be a struggle. Plus, first, you need to confirm that they are bed bugs and not some other insects. One way to identify them is by size. So, how big is a bed bug?
As a leading pest control company, we have dealt with bed bugs for years, so we will tell you how you can identify these pests. We will explore the sizes of the bed bugs from hatching to adulthood.
Let’s dive in and see how big bed bugs are, whether you can see them, and why they may get in your home.
How Big Is a Bed Bug?
Generally, bed bugs are about 5 to 7 mm 3/16 – 1/4 inch) in length and 2 – 3 mm (1/16 – ⅛ inch) in width. These are the average size measurements of an adult bed bug from the genus Cimex.
More specifically, the Cimex lectularius (the common bed bug) and Cimex hemipterus (the tropical bug). These two species are the primary culprits in household bed bug infestations. But how big are bed bugs can you see them?
While 5-7 mm is generally the maximum size of adult bed bugs, they come in various sizes, especially throughout their lifespan. In fact, you can only see adult bed bugs with your eyes without magnification.
Before reaching the adult lifecycle stage, bed bugs are undetectable to the naked human eye. It may take a while for people to notice a bed bug infestation.
Bed bug size vs. common household insects
If you suspect a potential bed bug infestation in your home, first, you need to confirm that it is indeed a one. Many tend to confuse bed bugs with other common insects found in homes.
This happens due to the similarities in looks and sizes between bed bugs and other insects. Some of the most commonly confused insects with bed bugs include:
- Swallow bug
- Flea
- Tick
- Carpet beetle adult
- Cockroach nymph
Out of all these insects, people tend to confuse bed bugs most often with ticks. Both pests have oval and flat shapes and are wingless with similar sizes.
Due to this, it is incredibly challenging to tell them apart if you don’t know what to consider. For instance, a question we often get asked is, do bed bugs have 8 legs? No, bed bugs have 6 legs, while ticks have 8.
How Big Can a Bed Bug Get? Sizes Through Lifecycle Stages
How big are bed bugs when they hatch? While adult bed bugs may reach up to 7 mm (similar size to an apple seed) and are easily visible, they are harder to detect in their juvenile stage.
The first stage bed bugs go through is hatching. When bed bugs hatch, they are about 1 mm (1/10 inch). After hatching from the eggs, bed bugs go through the nymph stage. This stage has several developmental cycles until the bed bug reaches adulthood.
Nymphs
When bed bugs are newly hatched, they are still small and off-yellow, almost translucent. In the first four weeks of their lifecycle, bed bugs go through five stages of development.
During this period, we refer to them as nymphs. As the nymphs go through their development into adult bed bugs, they grow and start to get a darker brown-reddish color.
The nymphs will be most visible right after feeding with blood as the translucent and flat shape expands and takes on a darker hue. Plus, as they feed and move through each stage, the nymphs molt until they reach the sixth and final stage: an adult bed bug. The size of bed bugs during the nymph stages are the following:
- 1st stage nymph 1.5 mm
- 2nd stage nymph 2 mm
- 3rd stage nymph 2.5 mm
- 4th stage nymph 3 mm
- 5th stage nymph 4.5 mm
Adult bed bugs
Upon reaching the sixth and final stage in their lifecycle, they can get as big as 5 to a maximum of 7 mm, about ¼ inches long. Adult bed bugs can be seen with the human eye, and you’ll be able to see them crawling around.
Adult bed bugs are easily recognizable due to their distinctive oval-shaped body. When they feed, the flattened part of their bodies expands, which increases their visibility.
Other Identifying Factors
Unfortunately, bed bugs, both in their nymph and adult lifecycle stages, feed only with blood. So, if you haven’t seen any yet, some other factors may point you to their presence, such as the following:
- Bites on your arms, face, neck, shoulders, and hands
- Molting skins, droppings, and dead bugs
- Blood stains on your sheets
By the time the bed bugs are visible, it will likely mean your home, office, hotel, etc., is already infested with these crawlies. The infestation process is likely in advanced stages, as it takes about 6-7 weeks for bed bugs to reach a visible state. This, in turn, means they have likely started laying eggs, which are not visible without magnification.
At this point, the best course of action is to contact a bed bug extermination company and let the professionals deal with the issue. If you are in Cleveland, Ohio, contact us for our guaranteed pest-free services, including:
- Heat treatment
- Steam treatment
- Chemical treatment
- Cryonite
Conclusion
So, how big is a bed bug? The answer will vary based on which stage of its life cycle it is. Generally, as we mentioned above, the average size of an adult bed bug may be 5 to 7 mm 3/16 – 1/4 inch) in length and 2 – 3 mm (1/16 – ⅛ inch) in width.
However, your space is most likely infested when they reach this size and are visible. So, if you notice any crawlies, make sure to contact us.