Huntsman spiders are usually about the size of a human hand, but the very largest species can reach roughly dinner‑plate width when fully stretched out.

Typical huntsman size

For most common huntsman species (especially those seen in homes in Australia and Asia):

  • Average body length is around 1.8 cm (about 0.7 inches).
  • Average leg span is up to about 12–15 cm (roughly 5–6 inches), which is similar to the width of an adult human hand.
  • Many people describe “normal” huntsmen as looking big but not absurdly huge once you’re close enough to see them properly.

Giant huntsman spider

There is one standout species that pushes the limits of “how big are huntsman spiders”:

  • The giant huntsman spider (Heteropoda maxima) is the largest huntsman and has the greatest leg span of any known spider.
  • Its leg span can reach about 25–30 cm (around 10–12 inches), roughly the size of a dinner plate or two U.S. dollar bills end to end.
  • The body length alone is about 4.6 cm (1.8 inches), making it much bulkier than typical house huntsmen.

What people actually see at home

Forum and Q&A discussions from Australians and others who live with these spiders give a grounded sense of scale:

  • Everyday adult huntsmen in homes are commonly reported at about 10–12 cm across (4–5 inches) in leg span.
  • Exceptionally large individuals are described as “as big as a man’s hand” or up to about 15 cm, with rare outliers approaching 20–25 cm for certain species.
  • Photos often look more terrifying because of forced perspective—objects like brooms or walls can make the spider seem several feet wide when it is not.

Are they dangerous?

Size aside, huntsman spiders look intimidating but are not considered highly dangerous to humans:

  • Most huntsman species are timid and prefer to run away rather than bite.
  • They do have venom for subduing prey, but bites to humans are usually mild, causing local pain and swelling rather than serious systemic effects.
  • In many regions, people tolerate them indoors because they help control insects like cockroaches.

TL;DR

  • Typical huntsman: body about 1.8 cm, leg span around 10–15 cm (hand‑sized).
  • Giant huntsman: body about 4.6 cm, leg span up to 25–30 cm (dinner‑plate‑sized).
  • They look scary but are generally shy and only mildly harmful to humans if disturbed.

Information gathered from public forums or data available on the internet and portrayed here.