The short answer: An adult guppy typically weighs between 0.5 and 3 grams (about 0.02 to 0.1 ounces), with females noticeably larger and heavier than males.
Guppy weight by type
These tiny fish vary by sex and life stage. Here are rough typical weights.
| Type (example) | Typical weight |
|---|---|
| Newborn fry | About 0.005 g (a few milligrams) |
| Juvenile | About 0.1 to 0.3 g |
| Adult male | About 0.5 to 1 g (0.02 to 0.035 oz) |
| Adult female | About 1.5 to 3 g (0.05 to 0.1 oz) |
| Gravid female | Up to roughly 3.5 g (0.12 oz) |
What affects guppy weight
- Sex. Females are larger and heavier than the slimmer, more colorful males.
- Age. Guppies grow quickly in their first few months before leveling off.
- Pregnancy. A gravid female carrying fry is noticeably heavier and rounder.
- Diet and water quality. Well-fed fish in clean, warm water grow larger.
- Strain. Some selectively bred fancy guppies run slightly bigger than wild types.
How guppy weight compares
A typical guppy weighs about the same as a single raisin or a paperclip, just a gram or two.
Frequently asked questions
Are female guppies heavier than males?
Yes. Female guppies are larger and can weigh roughly two to three times as much as males, especially when carrying fry.
How much does a baby guppy weigh?
Newborn guppy fry weigh only a few milligrams each, far less than a tenth of a gram.
Why do guppies weigh so little?
Guppies are small tropical fish, usually only 2 to 6 centimeters long, so even adults weigh just a gram or two.
