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Eight legs, many eyes, every fact sourced

Spiders, closer up.

Silk lighter than you’d believe, a spider that lives underwater in a bubble of air, a desert spider that cartwheels and a nearly vegetarian one. Every fact traced to a source and dated where it can change, plus a calm page on bites, games, printables, a page on the spiders of the Isle of Man and an eraser called Useless who would like everyone to stay very still.

Meet the species The big facts page

A brown garden spider in its web, with a pale cross pattern on its round abdomen
A garden spider, the UK’s most common orb web spider.Photo: Tweesmann, Jörg, Public domain, Commons
54,239spider species named worldwide World Spider Catalog, Natural History Museum Bern · checked 30 Oct 2026
680species in Great Britain and Ireland Lavery 2025, The spiders of Great Britain and Ireland checklist, Arachnology 20(3) (British Arachnological Society) · checked 30 Oct 2026
8eyes, for most spiders Australian Museum: How spiders see the world
235–240recorded on the Isle of Man Manx Wildlife Trust: Manx State of Nature 2024, invertebrates · checked 30 Oct 2026

The short version

Spiders are arachnids, not insects. They have eight legs instead of six, and a body in two parts instead of three. Britannica: Spider ‘Arachnid’ doesn’t just mean spider. There are 11 orders of arachnids, including scorpions and ticks; spiders are just one of them. Burke Museum, Seattle: Spider myths (by its spider curator)

All spiders but one are predators, feeding almost entirely on other small animals with jointed legs, especially insects. The exception, Bagheera kiplingi, is nearly vegetarian. Britannica: Spider

Spiders live on every continent except Antarctica (although bits of spider have been reported there), and as high as 5,000 metres in the Himalayas. Britannica: Spider (size and distribution) Spiders range from 0.5 mm to about 90 mm in body length. Britannica: Spider (size and distribution)

And in Britain they’re quietly useful. British spiders catch and eat many of the insects that bother us, such as houseflies, midges and wasps, and help stop farm pests building up. British Arachnological Society factsheet: Essential spider info If you’re wondering about bites, there’s a calm page on what the experts actually say.

A black-and-white striped male zebra spider on a leaf, facing the camera with its big front eyes
A male zebra spider: a jumping spider with excellent eyesight (photographed in California).Photo: Kaldari, CC0, Commons
Sources disagree: How many kinds of spiders are there?

The World Spider Catalog is updated as new species are named; Britannica’s total is a rounder, older-looking figure. New species are still being described, so treat both as snapshots. Every disagreement we found →

Start somewhere

Eight legs, many eyesTwo body parts, book lungs, no chewing and legs worked by blood pressure. Silk & websOrb webs in an hour, nets, diving bells and the toughest silk known. Egg sac to adultSilk egg sacs, moulting, and spiderlings that fly on the wind. Hunters & trickstersAmbushers, jumpers, swimmers and a spider that cartwheels. Bites, calmlyWhat the Natural History Museum says about spiders and people. Isle of ManAround 235 species, and a pirate spider found in Onchan. Wolf spidersBig eyes, egg sacs on board, and why most need a microscope to name. Spiders as petsResponsible tarantula keeping, from the British Tarantula Society and RSPCA.

Tile pictures are credited on their pages and on the credits page.

Behind the shed

Things to do while the kettle boils

All games →

The spider that lives underwater

The water spider is the only spider that spends its life underwater, in a bell-shaped web of silk that it fills with air: a ‘diving bell’. The Wildlife Trusts: Water spider It collects air from the surface in the hairs on its body and carries it down to fill the bell. The Wildlife Trusts: Water spider

And the one that cartwheels

The golden wheel spider of Namibia escapes danger by cartwheeling down sand dunes, spinning 44 times a second. Britannica: Spider (size and distribution) Meet more on the species page.

An old engraving of water spiders underwater among water plants, with an air-filled silk bell
Water spiders and an air-filled silk bell, from Alfred Brehm’s Tierleben.Illustration: Alfred Brehm, Public domain, Commons
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