What Do Bed Bugs Look Like? A Detailed Guide to Identifying Bed Bugs

Bed bugs are small, flat, parasitic insects that feed on human blood. These sneaky pests are excellent at hiding, often living in mattresses, bed frames, furniture, and even suitcases. Knowing what bed bugs look like is critical for identifying an infestation before it gets out of control. This comprehensive guide covers everything you need to know about what bed bugs look like at each life stage.

What Do Bed Bugs Look Like? Key Identification Characteristics

Bed bugs have a number of key characteristics that set them apart from other household insects. The main features to look for when identifying bed bugs include:

Size and shape: Adult bed bugs are oval-shaped, wingless insects that grow to about the size of an apple seed. Their flat bodies are perfect for fitting into tiny crevices. Newly hatched bed bugs are about the size of a poppy seed.

Color: Bed bugs may be brown, red or purple in color. They are often described as looking more “rusty” than other household bugs. Their color helps camouflage them in places like mattress seams and furniture cracks.

Body markings: Bed bugs have plain bodies without any patterns, stripes, or markings. Their body is divided into three segments and is covered in short, golden hairs.

Flat profile: Since bed bugs feed by inserting their needle-like mouthparts into the skin, they are flat to fit into tiny spaces and cracks to reach hosts. Their bodies become plump and elongated after feeding.

Six legs: Like all insects, bed bugs have six jointed legs. Their hind legs have thicker sections which help propel them through tight spaces.

Antennae: Bed bug antennae are four segmented, with the last segment divided into several parts at the tip. They tuck into recesses when not in use.

Musty, sweet odor: Large bed bug infestations give off a musty, sweet, “buggy” odor from their scent glands. But a minor infestation is unlikely to have an obvious smell.

Bites: Bed bug bites often form red, itchy welts on the skin in small clusters or lines. But bites may not appear on everyone.

Keep these key identifiers in mind when inspecting for bed bugs. The insects can appear slightly different depending on their life stage and feeding status.

Bed Bug Appearance by Life Stage

Bed bugs go through five nymph stages before reaching the adult stage. Each progressive molt makes them larger. Here is what bed bugs look like at each stage:


  • Size: 0.5mm, about the size of a pinhead
  • Shape: Oval and pale white
  • Features: Laid in cracks and crevices, cemented to surfaces in clusters of 10-50 eggs

Bed bug eggs are soft, oval, and a pale white color. They are tiny, about 0.5mm long, or roughly the size of a pinhead. Females cement clusters of eggs in cracks and crevices along bed frames, mattresses, and furniture. The eggs have a sticky surface that adheres them to these areas.

Under a microscope, bed bug eggshells have a textured, net-like cell pattern on the outer surface. But they appear smooth and white to the naked eye. Newly laid eggs must be magnified to be visible.


  • Size: 1mm upon hatching, 1.5-4mm as adults
  • Color: Nearly colorless to cream/tan, later taking on a red-brown hue
  • Shape: More rounded body shape than adults
  • Markings: Undeveloped wing pads on thorax

Bed bug nymphs look like tiny versions of the adults, changing from nearly colorless upon hatching to a cream/tan, and finally to a red-brown hue as they mature. The body shape starts off more rounded compared to elongate adult bed bugs. Small wing pads can be seen on the thorax.

First stage nymphs are around 1mm long. Second stage nymphs grow to 2mm, third stage to 2.5mm, fourth stage to 3mm, and fifth stage to 4mm. Without a microscope, the first few nymph stages are tiny enough that they may be mistaken for dust particles.


  • Size: 5-7mm, similar to an apple seed
  • Color: Reddish-brown to brownish-purple
  • Shape: Flattened oval shape, sometimes described as “turtle-like”
  • Markings: None

Adult bed bugs reach 5-7mm in length once fully grown, about the size of an apple seed. Their color ranges from reddish-brown to brownish-purple. Adults have an elongated, flattened, oval-shaped body, with some describing them as “turtle-like.” The body is made up of three visible segments, and covered in short, microscopic hairs.

As adults, bed bugs do not have any markings, spots, bands, or stripes. Their body is plain apart from inconspicuous, fine hairs. After feeding, the adult bodyswells and becomes more red as it fills up with blood.

Appearance Differences After Feeding

A hungry bed bug is nearly flat, allowing it to hide away in cracks and crevices. After feeding on blood, its body plumps up and becomes more elongated and red.

Here are the main physical changes bed bugs go through after feeding:

  • Body swells and elongates from flat to plump.
  • Body color changes to a deeper red/purple hue as insects fill with blood.
  • The exoskeleton stretches to accommodate the larger, blood-engorged abdomen.
  • Nymphs molt into larger instars after getting enough blood meals.
  • Egg production and mating increases in well-fed adults.

The engorged appearance after feeding is one of the best times to spot bed bugs. The enlarged, redder profile makes them more visible as they seek out a new hiding spot.

Use the identification points in this guide to inspect closely in areas where bed bugs may hide or travel. The signs will appear subtle at first, but become more obvious as the infestation grows. Catching bugs early makes treatment more successful before they multiply into the thousands.

Where Do Bed Bugs Hide? Common Hiding Places

Knowing where bed bugs like to hide can make inspecting for an infestation much easier. Concentrate your search in these prime bed bug hiding spots:

  • Mattress seams and tufts – The crevices in mattress stitching provide the perfect tight, dark spaces for bed bugs to hide and nest near a food source.
  • Box spring encasements – Box springs contain ample nooks and crannies inside for bed bugs to tuck into, especially underneath or near the edges.
  • Bed frames and headboards – The cracks, corners, screw holes, and wooden slats of bed frames offer harborages to hide.
  • Furniture seams and upholstery – Sofas, chairs, cushions, and other upholstered furniture make common hiding places away from the bed.
  • Behind headboards and nightstands – The space where furniture touches walls is appealing since bed bugs can crawl up the walls.
  • Moldings and wall hangings – Picture frames, outlets, molding cracks, peeling wallpaper and similar decor provide concealment.
  • Carpet edges and under flooring – Bed bugs often spread between adjoining rooms under carpet edges or loose sections of wood flooring.
  • Luggage and other belongings – Suitcases, backpacks, purses, and clothes can hide bed bugs when traveling and spread an infestation.

Knowing the favorite hiding spots improves the chances of discovering the early warning signs. Inspect crevices with a flashlight and magnifying glass. A thorough inspection along baseboards, furniture, outlets and mattresses can help identify an issue while it remains small and manageable.

Signs of Bed Bugs Beyond Live Insects

Seeing live bed bugs is just one clue to an infestation. Finding their shed skins, blood spots and eggs can also confirm their presence.

Shed skins – As nymphs outgrow their exoskeletons, they molt and leave behind whitish, translucent, husk-like skins. These papery skins accumulate in bed bug hot spots.

Blood spots – After feeding, bed bugs often defecate dark reddish to brown fecal spots on surfaces. These spots may bleed and smear if wiped.

Eggs and egg shells – Empty whitish egg shells or pearl-like eggs cemented in cracks indicates reproduction. Use a flashlight and magnifying glass.

Musty sweet odor – A distinct “buggy” aroma from pheromones and scent glands may be noticeable in severe infestations.

These signs help confirm bed bugs are hiding out even if the insects themselves remain unseen. Pay attention to any of these markers during inspections and when cleaning. Eliminating bed bugs means addressing these traces as well as killing live bugs.

Common Lookalikes: Insects Mistaken for Bed Bugs

Several other household insects get mistaken for bed bugs due to physical similarities. But these lookalikes have key differences that set them apart:

Carpet beetles – While similar in size, carpet beetle larvae have dense tufts of hair on their posterior end which bed bugs lack. They feed on natural fibers, not blood.

Spider beetles– These round-shaped bugs have visible head and leg segments unlike bed bugs’ oval shape. They are also hairy. They feed on plants and mold, not blood.

Bat bugs – Almost indistinguishable from bed bugs in appearance, bat bugs feed on bats, not humans. Telltale signs like bat droppings help differentiate them.

Dust mites – Microscopic arachnids related to spiders and ticks, dust mites feed on dead skin cells, not blood. They do not bite humans.

Booklice – Often mistaken for bed bug nymphs, these tiny gray or white insects infest damp books, cardboard, and moldy belongings, not beds. They do not bite.

Take a close look at any suspect insect’s characteristics to rule out lookalikes. Proper identification is key to addressing the right pest problem. Getting confirmation from a professional can provide peace of mind.

FAQ About Identifying Bed Bugs

What do baby bed bugs look like?

Newly hatched bed bug nymphs look like tiny, rounded versions of the adult insects, ranging from a nearly colorless appearance to light tan. Early instars are only 1mm long, about the size of a poppy seed. Immature bed bugs do not have an elongated shape until later molts.

Are bed bug bites an identifying sign?

While bed bug bites may help raise suspicion, they do not confirm an infestation. Bites and rashes may take days to appear, can resemble other insect bites, and some people do not react at all. Bites should not be used as definitive proof.

What is the best way to find bed bugs?

The best technique involves methodically inspecting common hiding places in crevices of mattresses, bed frames, furniture, and baseboards using a flashlight and magnifying lens. Look for live bugs, eggs, blood spots, skins, and the musty scent.

Do bed bugs come out in the daytime?

Bed bugs are most active at night when hosts sleep, but they can crawl out to seek a meal during daytime hours if hungry. Their flattened shape and pale color helps them hide out during the daytime as well.

How fast can bed bugs spread?

Bed bugs reproduce quickly, with each female laying up to 5 eggs per day and over 200 in her lifetime. They can crawl fast to spread between rooms and hitchhike on belongings. Early detection when infestations are contained to the bed area is key.

The Takeaway on Bed Bug Identification

Being able to accurately identify bed bugs is a crucial step in preventing major infestations. Look for the telltale oval shape, flat profile, rusty-red color, lack of markings, and clusters of eggs in cracks and crevices near sleeping areas. The sooner these sneaky pests are detected, the better chance you have of eliminating them and preventing bites. Getting confirmation and treatment recommendations from a pest control professional can provide peace of mind.

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