What do bed bugs look like?

Knowing exactly what bed bugs look like — at every stage — is the quickest way to confirm or rule out an infestation, because unlike bites, the insects and their eggs are hard to mistake once you know the signs.

Adult bed bugs

An adult bed bug is about the size and shape of an apple seed — roughly 4–5mm long, flat, oval, and reddish-brown (mahogany). After feeding they swell up, become rounder and turn a darker blood-red. They have no wings and can’t fly or jump; they crawl. That flat shape is why they can squeeze into the thinnest cracks and seams during the day.

Nymphs (young bed bugs)

Newly hatched nymphs are tiny — around 1–1.5mm — and translucent or pale straw-coloured, which makes them very hard to spot, especially before they’ve fed. They darken as they grow through five stages to adulthood. If you can see pale, almost see-through specks moving in the bed frame, those are likely nymphs.

Eggs

Bed bug eggs are about 1mm long, pearly white, and shaped like a grain of rice. They’re laid in clusters, glued into cracks and crevices — mattress seams, bed-frame joints, behind headboards. To the naked eye a cluster looks like a scattering of tiny white specks.

Things people mistake for bed bugs

• Carpet beetles — rounder, often patterned (mottled black/white/brown), and their larvae are fuzzy; they don’t bite
• Fleas — dark, narrow, and they jump (bed bugs can’t); usually linked to pets
• Cockroach nymphs — faster-moving and a different body shape
• Spider beetles and bat bugs — close relatives that need an expert to tell apart
• Booklice — minuscule, pale, and harmless

Still not sure?

Our guide to spotting the signs covers exactly where to look and what the evidence looks like. If you’ve found an insect you can’t identify, a professional inspection will confirm it for certain before you spend anything on treatment — submit a request through our free matching service to get a vetted local specialist to take a look.