What Does Lice Look Like? Pictures, Sizes & Identification

Spotting head lice isn’t as hard as people think—once you know exactly what to look for. These tiny parasites are about the size of a sesame seed, and they come in colors that blend surprisingly well with most hair.

Adult lice size: sesame seed (2–4 mm) ·
Lice color: grayish-white or tan ·
Nits color: yellow, brown, or white ·
Legs per louse: six with hooklike claws ·
Nits attachment: glued to hair shafts

The table below consolidates the most essential identification markers for head lice and their eggs.

What Do Head Lice Look Like?

Adult head lice are small but visible to the naked eye. They measure roughly 2–4 millimeters—about the size of a sesame seed. Their color typically ranges from grayish-white to tan, which allows them to blend into most hair shades.

Head lice may appear tan, gray, or white depending on how recently they’ve fed. Each louse has six legs, and those legs end in tiny hooklike claws designed specifically for gripping hair strands.

— Harvard Health, academic medical center

Up close details

Each louse has six legs, and those legs end in tiny hooklike claws designed specifically for gripping hair strands. This claw structure is what makes lice so difficult to remove by hand—they can grip multiple hair diameters at once. Their bodies are flattened, which helps them move quickly through hair close to the scalp.

In hair

Head lice tend to stay within half a centimeter of the scalp, where they feed on blood. They’re most commonly found behind the ears, along the neckline, and at the base of the head. Lice Clinics of America (a specialist lice treatment provider) notes that checking within this zone gives the best chance of spotting live lice.

Understanding the precise symptoms that can accompany infestations helps contextualize why early detection matters for both comfort and treatment timing.

On skin or finger

If you pick up a louse on your finger, you’ll notice it can move quite fast. Lice don’t jump or fly—they crawl—but they can dart through hair quickly when disturbed. On skin, you might see small scratch marks from itching, especially around the nape of the neck and behind the ears.

What Do Lice Eggs Look Like?

Nits are the eggs of head lice, and they’re often easier to spot than live lice because they don’t move. According to HSE.ie (Health Service Executive of Ireland), nits can be yellow, brown, or white. They’re tiny oval shapes—typically 0.5–2 millimeters—that attach directly to hair shafts with a glue-like substance.

Nits vs dandruff

The key difference between nits and dandruff is attachment and movement. Lice Clinics of America (a specialist lice treatment provider) emphasizes that nits stick firmly to hair and won’t brush off easily, whereas dandruff flakes away with a gentle shake. If something doesn’t move when you blow on it or flick it, that’s a strong sign it’s not a nit.

Color variations

Live nits appear darker—yellow or brown—while empty egg casings are white or light yellow and become more visible on darker hair. Medical News Today (a peer-reviewed medical information publisher) notes that this color difference can help you distinguish between a active infestation and old nits that have already hatched.

Head lice are parasitic insects that feed on human blood. The insects lay eggs on hair shafts close to the scalp, and these eggs hatch after about a week.

— Medical News Today, peer-reviewed medical information publisher

Attachment to hair

Female lice lay eggs close to the scalp and secure them with a substance similar to glue. LiceDoctors (a professional lice removal service) reports that this attachment is so strong that nits don’t fall off naturally—you need to pull them out manually or use a specialized comb.

How Do You Tell If It’s Lice?

Beyond the visual appearance, there are signs that suggest an infestation is underway. Itchy scalp is the most common symptom, caused by an allergic reaction to louse saliva. Mayo Clinic (a top-ranked academic medical center) identifies scratching, particularly at night, as a hallmark sign. If you’re noticing persistent itching behind the ears or at the nape of the neck, it’s worth doing a closer check.

Head lice are not dangerous, but they are contagious and spread quickly through close personal contact and sharing of hats, combs, and other personal items.

— Mayo Clinic, top-ranked academic medical center

Symptoms like itching

Not everyone reacts the same way to head lice. Some people experience intense itching, while others may have minimal symptoms even with a active infestation. The allergic reaction develops over time, so new cases sometimes go undetected for a week or two.

Those experiencing persistent respiratory issues alongside scalp symptoms may benefit from reviewing natural clearance methods to rule out unrelated conditions.

Visual checks

Use a fine-toothed lice comb on damp hair, working from the scalp outward. Medical News Today (a peer-reviewed medical information publisher) recommends combing in sections and wiping the comb after each pass to inspect what comes out. Look for live lice (moving) and nits (stationary but glued).

Early signs

The first signs often show up as a crawling sensation on the scalp or slight redness around bite areas. Early-stage lice (nymphs) are smaller than adults—about 1–2 millimeters—but they’re already mobile and feeding.

What Can Be Mistaken for Hair Lice?

Several common conditions can mimic the appearance of head lice, leading to unnecessary treatment or worry.

Dandruff

Dandruff flakes are irregular in shape and size, and they shift easily when touched or blown on. Nits are uniform and stuck firmly to the hair shaft. If you’re unsure, dampen the hair—dandruff will float or detach, while nits remain attached.

Product buildup

Hair products, especially gels and mousses, can create small white or yellowish specks along the hair. These particles rinse out with water and don’t have the oval shape of a nit. They also don’t cluster near the scalp the way nits do.

Other insects

Fleas or booklice (small insects that sometimes live in bedding) might occasionally transfer to hair, but they don’t have the distinctive claw structure for gripping hair. Fleas are more mobile and can jump, while lice cannot. Booklice prefer humid environments and aren’t adapted for life on a human scalp.

What Does Lice Look Like in Dark Hair?

Head lice can camouflage by matching hair color, which makes them harder to spot in darker hair. According to Medical News Today (a peer-reviewed medical information publisher), lice may appear darker or lighter depending on the individual hair shade. On very dark hair, they often look tan or brown rather than grayish-white.

Color adaptation

Lice pigmentation isn’t fixed—they adapt to some degree to their host’s hair color. This is a survival mechanism. In blonde hair, lice tend to look lighter; in darker hair, they blend in with tan or brown tones.

Visibility challenges

In very dark hair, empty nit casings—which are white or light yellow—often stand out more than live nits or live lice. Checking under good lighting and using a magnifying glass can help. A lice comb is particularly useful in dark hair because it brings lice and nits to the surface as you comb through.

Frequently asked questions