Largest Spiders in the World: Goliath Birdeater and Others

How spider size is measured

Spiders are measured in three main ways: weight, body length (head and abdomen, without the legs) and leg span, the distance from the tip of one front leg to the tip of the opposite back leg. Heavy-bodied tarantulas win on weight and body length, while long-legged huntsman spiders win on leg span.

Records need care. Many famous figures come from spiders raised in captivity, where they are well fed, and leg spans are hard to measure on a living spider. Sizes reported from photos, or by frightened people who saw a spider in a house, are almost always too large.

1. Goliath birdeater: the heaviest spider

The Goliath birdeater (Theraphosa blondi) lives in rainforests of northern South America, including Venezuela, Guyana, Suriname, French Guiana and northern Brazil. It is the largest spider by mass and body length: the record weight is about 175 g (6.2 oz), a little more than a baseball, the body can reach 13 cm (5.1 in), and the leg span is up to about 28–30 cm (11–12 in).

Despite its name, it rarely eats birds; see do Goliath birdeaters eat birds? It lives in deep burrows on the forest floor and feeds mostly on large insects, earthworms and other invertebrates, plus occasional frogs, lizards and small rodents. Females can live 15–25 years, while males usually die within a few years of reaching maturity.

When threatened, a Goliath birdeater makes a hissing sound by rubbing bristles on its legs together, rears up to show its fangs and kicks irritating hairs off its abdomen.

2. Giant huntsman spider: the widest leg span

The giant huntsman spider (Heteropoda maxima) was described only in 2001, by German arachnologist Peter Jäger, from caves in Laos. It has the widest leg span of any known spider, up to about 30 cm (12 in), but a far smaller body than the Goliath birdeater, about 4.6 cm (1.8 in) long.

Like other huntsman spiders, it has long legs that twist forward like a crab’s, and it does not build a web to catch prey. Its pale color and long legs suggest it is adapted to life in caves, although it seems to live near cave entrances rather than in total darkness.

3. Other giant Theraphosa tarantulas

The Goliath birdeater has two close relatives of similar size in the same genus. The pinkfoot Goliath (Theraphosa apophysis) of Venezuela, Colombia and Brazil reaches about the same size; its young have pink-tipped legs that fade as they grow. The burgundy Goliath (Theraphosa stirmi) of Guyana and Brazil is another heavy-bodied giant. Some keepers claim one of these outgrows T. blondi, but no reliable data settle the question.

4. Brazilian salmon pink birdeater

The Brazilian salmon pink birdeater (Lasiodora parahybana) comes from the Atlantic Forest of northeastern Brazil, where it is known from a small area of Paraíba state. It is usually ranked as the fourth-largest tarantula. Its leg span can reach about 28 cm (11 in), with males having longer legs and females much heavier bodies; large females can weigh over 100 g (3.5 oz). Mature spiders are black with salmon-pink hairs on the legs and jaws.

5. Baboon spiders of Africa

Africa’s big tarantulas are called baboon spiders, because their leg segments are said to resemble a baboon’s fingers. The king baboon spider (Pelinobius muticus) of East Africa is a rusty-orange burrower that can reach a leg span of about 20 cm (8 in). It is highly defensive and makes a loud hissing sound when disturbed.

The Hercules baboon spider (Hysterocrates hercules), described in 1900 from Nigeria, often appears in lists of the world’s biggest spiders. However, it is known from very few specimens, so the large sizes quoted for it online cannot be checked.

6. Golden orb-weavers: the largest web-spinners

The biggest spiders that catch prey in webs are the golden orb-weavers of the tropics. Females of the giant golden orb-weaver (Nephila pilipes) of Asia and Australia have bodies of about 3–5 cm (1.2–2 in), while males are tiny, only about 5–6 mm. Their strong golden silk webs can be more than 1 m (3 ft) across.

The largest web-spinner known is Trichonephila komaci of southern Africa and Madagascar, described in 2009. Females have a body about 4 cm (1.6 in) long and a leg span of about 12 cm (4.7 in).

7. Brazilian wandering spiders: big and venomous

Wandering spiders (genus Phoneutria) of Central and South America are large hunting spiders with leg spans of about 13–18 cm (5–7 in) and bodies of 17–48 mm (0.7–1.9 in). Unlike most giant spiders, they have venom that is medically significant to people. Most bites cause only local pain, but serious cases happen, mainly in young children. Read more in our list of the most venomous spiders.

Largest spiders in the United States

North America’s biggest spiders are much smaller than the tropical giants. The heaviest are tarantulas of the Southwest and south-central states, such as the Texas brown tarantula (Aphonopelma hentzi), which can have a leg span of more than 10 cm (4 in). Males are often seen wandering in the fall as they search for females.

The Carolina wolf spider (Hogna carolinensis) is the largest wolf spider in North America, with females measuring about 22–35 mm (0.9–1.4 in) in body length. The dark fishing spider (Dolomedes tenebrosus), found in woodlands of the eastern US and Canada, has females with bodies up to about 26 mm (1 in) and long legs spanning roughly 5–9 cm (2–3.5 in). The golden silk orb-weaver of the Southeast is one of the country’s largest web-spinners.

Largest spiders in Europe and the UK

Europe’s largest spiders live mainly in the south. The tarantula wolf spider (Lycosa tarantula) of Italy, Spain and other Mediterranean countries is a burrowing wolf spider whose females reach about 30 mm (1.2 in) in body length; it is the original “tarantula” that gave the word to the much larger American spiders. The Spanish funnel-web spider (Macrothele calpeiana) of southern Spain, Portugal and Gibraltar is another of Europe’s biggest spiders, and the only spider protected under European Union law.

In the UK, the cardinal spider (Tegenaria parietina) is usually named as the largest native species, with females up to about 20 mm (0.8 in) long and much longer legs. The more familiar giant house spider, seen running across floors in late summer and autumn, has a leg span of about 45 mm (1.8 in) in females and up to about 75 mm (3 in) in long-legged males. The rare fen raft spider, protected by law in Britain, is another of the country’s largest spiders.

Were there giant prehistoric spiders?

Not as far as the fossil record shows. In 1980, a fossil from Argentina was named Megarachne and described as a giant spider with a body about 34 cm (13 in) long. When the fossil was re-examined in 2005, it turned out to be a eurypterid, or sea scorpion, a very different animal. The largest fossil spiders found so far, such as Mongolarachne from China, had bodies only about 2.5 cm (1 in) long, far smaller than today’s tarantulas.

Are giant spiders dangerous?

Size has little to do with danger. Tarantulas, including the Goliath birdeater, have large fangs and can give a painful bite, but their venom is weak to people and is usually compared to a wasp or bee sting. Many American tarantulas also flick barbed hairs from their abdomen that can irritate skin and eyes. Most large spiders bite only when handled or trapped, and the safest approach is simply to leave them alone. Anyone with a severe reaction to any spider bite should seek emergency medical help immediately (911 in the US, 112 in the EU, 999 in the UK).

Largest spiders compared