Snails come in an enormous range of sizes — from microscopic species barely visible to the naked eye, to the giant African snail which can reach the length of a human forearm. Here's how the most common snail species compare.

Garden snail crawling on a green leaf, showing its banded spiral shell
A garden snail (Cornu aspersum) on a leaf. Like all land snails, it uses its 25,000-tooth radula to rasp through plant material. Photo: Unsplash

Garden Snail Size

The common garden snail (Cornu aspersum) is mid-sized among land snails:

  • Shell diameter: 25–40 mm (roughly the size of a 50p coin)
  • Body length (extended): 7–10 cm
  • Weight: 5–25 grams

Size Comparison Table

SpeciesShell SizeBody LengthHabitat
Dwarf pond snail4–8 mm~1 cmFreshwater
Garden snail25–40 mm7–10 cmLand/Garden
Roman (Burgundy) snail40–55 mm10–15 cmLand/Woodland
Giant African SnailUp to 200 mmUp to 30 cmLand/Tropical
Giant whelk (sea snail)Up to 700 mmBody ~30 cmMarine
📏 Fun size fact: The giant African land snail (Achatina fulica) is the largest land snail in the world. The biggest recorded specimen had a shell 39.3 cm long and weighed nearly 900 grams — heavier than most mobile phones.
Extreme macro photography of a small creature showing fine surface detail
The microscopic detail of a snail's radula can only be seen under magnification — the individual denticles (teeth) are finer than a human hair. Photo: Unsplash

Snail vs Human: A Scale You Can Imagine

  • A garden snail shell is roughly the size of a large grape or a 50p piece
  • A giant African snail at full size is roughly the length of your forearm
  • The largest known fossil snail was over a metre in diameter
  • A microsnail (family Truncatellinidae) fits comfortably on the tip of a pencil
Collection of various sea shells on a sandy surface showing diverse spiral shapes
A selection of gastropod shells showing the enormous variety in snail shell shape, size, and pattern. All were built by the snail's mantle using calcium carbonate. Photo: Unsplash

Does Size Affect Tooth Count?

Generally yes — larger snails have longer radulae with more tooth rows, meaning more total teeth. The giant African snail is thought to have one of the highest tooth counts of any land snail species, exceeding 25,000 teeth in large adults.