Spider Identifier: What Kind of Spider Is This?

Which spiders are dangerous, and when a bite needs a doctor

Most spiders are harmless to people: the jaws of most are too small to bite through an adult’s skin (UC IPM). CDC’s page on venomous spiders in the US names two, the black widow and the brown recluse. Know these, and these signs:

Common spiders compared

Compare the web, the size with the legs, the markings and where it turned up. No single clue settles it: the violin mark misleads, and some funnel weavers can only be told apart under a microscope (UC IPM).

Coin sizes with the legs stretched out are the University of Kentucky’s; the other sizes and the rest of the table come from that chart, UC IPM, UC Riverside, Penn State, the University of Minnesota, the Missouri Department of Conservation, Washington State, Colorado State, UF/IFAS, Texas A&M AgriLife and the US Army Public Health Center (see sources). “Body” means the body without the legs. Scroll sideways on a phone to see every column.

How to tell spiders apart

Six clues do most of the work. The questions above ask about each one.

• The web

  A messy cobweb points to cobweb spiders (house spiders, widows, false widows) or cellar spiders; a flat sheet with a funnel at one side to grass spiders and other funnel weavers; a round web of circles and spokes to orb weavers (UC IPM; University of Minnesota). Wolf, jumping and fishing spiders build no web to catch prey (Missouri Dept. of Conservation; UC IPM).

• The eyes

  Most spiders have eight eyes. Recluses have six, in three pairs, and woodlouse spiders six, in two groups of three (UC IPM). Jumping spiders have two big eyes facing forward on a flat face (University of Kentucky). At night, a flashlight held beside your own eyes makes a wolf spider’s eyes shine back (Missouri Dept. of Conservation).

• The legs

  Recluses have legs of one even color, with fine hairs and no spines; bands, stripes or thick spines rule a recluse out (UC IPM; UC Riverside). Very long, thin legs on a tiny body point to a cellar spider, or to a harvestman if the body is one oval piece (University of Kentucky; Missouri Dept. of Conservation).

• Color and markings

  Markings help but can mislead: people see violins on many harmless brown spiders (UC IPM). A red or orange hourglass on the underside of a shiny black, round spider is the black widow’s mark (UC IPM). The common bold jumping spider is fuzzy and usually black, often with white spots (Missouri Dept. of Conservation).

• Where and when

  Brown recluses are established only in 16 central and southern states (Penn State), fishing spiders live near water (University of Minnesota), and orb weavers turn up on porches and in gardens, especially in late summer (University of Kentucky). Big spiders that appear indoors are often males searching for females (UC IPM).

• Is it a spider at all?

  Spiders have eight legs and two body parts, and no wings or antennae (UC IPM). A harvestman has one oval body and two eyes (Missouri Dept. of Conservation), and a camel spider has huge jaws and leg-like palps (UC IPM): neither is a spider.

Spider photos to compare

Real, credited photos. Each card opens a guide that covers that spider; a card without a link is a guide still being written.

Already know which spider it is?

Go straight to the guides for that spider.

• Common house spider

  A small brown spider with a round, patterned abdomen that stays in a messy cobweb in a corner, a window or the basement.

  • Common House Spiders: How to Identify Them and Why They Come Inside
  • What a common house spider egg sac looks like
  • House spider or brown recluse?

• Cellar spider (daddy longlegs spider)

  A pale spider with a tiny body on very long, thin legs, hanging in a loose web in a corner of a basement or ceiling.

  • The spider with very long, thin legs
  • Why a spider holds a ball of eggs in its jaws

• Wolf spider

  A hairy brown or gray hunter, often striped, that runs fast across the ground or the floor and builds no web.

  • Wolf Spiders: Identification, Bites and the Babies on Their Backs
  • Wolf spider or brown recluse?

• Jumping spider

  A compact, often fuzzy spider with big front eyes that hunts by day on walls, windows and plants, and jumps.

  • Black Spider With White Spots? How to Identify Black Spiders by Markings
  • The small black spider that jumps

• Orb weaver (garden spider)

  A web-sitting spider, often large and colorful, in a round, wheel-shaped web in a garden or on a porch, most noticeable in late summer.

  • The big yellow and black garden spider
  • The big spider with the golden web

• Grass spider (a funnel weaver)

  A fast, striped brown spider that waits in the funnel of a flat sheet web on lawns and low plants, and sometimes comes indoors in the fall.

  • Grass spider or brown recluse?
  • Grass spider or wolf spider?

• House funnel weaver (giant house, hobo or barn funnel weaver)

  A big, long-legged brown spider that builds sheet webs with a funnel in basements, garages and window wells; wandering males run across floors.

  • The big spiders running across the floor
  • Hobo spider or brown recluse?

• Yellow sac spider

  A small, pale yellow spider with dark jaws that roams walls and ceilings at night and hides by day in a silk sac in a corner.

  • The pale spider on the wall or ceiling
  • Yellow sac spider or brown recluse?

• False widow (false black widow)

  A shiny, chocolate-brown spider with a round body like a widow’s but no red hourglass, common inside homes.

  • Is a shiny black spider in the house a false widow?
  • Is a shiny dark spider in the house a black widow?

• Black widow

  A shiny black spider with a round abdomen and a red hourglass underneath, in a messy web low down in a sheltered spot. Its bite needs medical care.

  • Is it a black widow? How to check
  • How to recognize a black widow

• Harvestman (daddy longlegs): not a spider

  A spider relative with one oval body and very long legs. It has two eyes, makes no silk and has no venom.

  • Are daddy longlegs dangerous?
  • The long-legged spider in the basement (a cellar spider)

• Fishing spider

  A very large, hairy brown spider found near water, on rocks, logs and tree trunks, that can run on water. It builds no web.

  • Fishing spider or wolf spider?

• Brown recluse (or another recluse)

  A plain tan to dark brown spider, about the size of a quarter with its legs out, that hides in clutter, boxes and closets. Its bite can need medical care.

  • Spiders That Look Like Brown Recluses: How to Tell Them Apart
  • Where brown recluses live
  • Brown Recluse Bite: Pictures, Stages, Symptoms and When to Get Care

• Parson spider

  A dark ground spider with a white band on its abdomen that runs fast across floors at night, often indoors in the fall.

  • The black spider with white spots or a white band
  • How to tell which black spider you have

• Woodlouse spider

  A red-orange spider with a pale grayish rear and big, forward-pointing fangs, found under rocks and logs and sometimes indoors. It builds no web.

  • The red spider with big fangs in the basement
  • Is a woodlouse spider a brown recluse?

• Brown widow

  A mottled tan, brown and gray widow with an orange hourglass underneath and spiky egg sacs, common outdoors in the South and Southern California.

  • What a brown widow looks like, and how dangerous it is
  • The spiky egg sac of the brown widow

• Southern house spider

  A southern spider: the dark gray female hides in a crack inside a flat, woolly web on the house, and the tan, long-legged male is often mistaken for a brown recluse.

  • Southern house spider or brown recluse?
  • The spider that makes the thick web on the house wall

• Green lynx spider

  A bright green hunting spider with long, spiny legs that leaps among shrubs and flowers in the southern United States.

  • The bright green spider on the shrubs
  • The bright green spider on Texas plants

• Tarantula

  A very large, hairy brown spider of the Southwest and south-central US. The ones seen out in the open are usually males looking for mates.

  • Are tarantulas dangerous?
  • Tarantulas in California

• Camel spider (windscorpion): not a spider

  A fast, yellowish-brown arachnid of dry western and southwestern areas, with huge pincer-like jaws and leg-like palps that make it look ten-legged. It has no venom.

  • What Does a Spider Bite Look Like? Identification, Stages & When to Worry (2026)

Spider identification questions