What does a bedbug look like in size? - briefly
A bedbug measures roughly 4–5 mm (0.16–0.20 in) in length, comparable to an apple seed, with a flat, oval body. Its width is about 2–3 mm, giving it a small, pancake‑like appearance.
What does a bedbug look like in size? - in detail
A common bed bug (Cimex lectularius) measures roughly 4 to 5 mm in length when fully grown, comparable to the width of a grain of rice. Its body is flattened, oval, and reddish‑brown, expanding to about 6 mm after feeding due to blood ingestion. Nymphs are smaller, ranging from 1 mm in the first instar to 3 mm in later stages, and their coloration is lighter, often tan or pale brown. Adult males and females share similar dimensions; females may appear slightly broader because of a fuller abdomen when gravid.
Key size characteristics:
- Length: 4–5 mm (adult), 1–3 mm (nymphs)
- Width: 2–3 mm (adult)
- Post‑meal expansion: up to 6 mm long, 3–4 mm wide
- Body shape: dorsoventrally flattened, facilitating movement within fabric seams and mattress crevices
These dimensions allow the insect to hide in tiny cracks, thread seams, and the edges of bedding, making visual detection difficult without magnification. A handheld magnifying lens or 10× loupe reveals the distinct, bean‑shaped silhouette and the characteristic reddish hue that darkens after a blood meal.