Animal
Goldfish
The goldfish is a pet fish that lives in ponds and tanks. Its wild family comes from East Asia, where they are greenish-brown.
The goldfish is a small member of the carp family that people in China tamed centuries ago, by the time of the Song dynasty (960–1279). Wild goldfish are greenish-brown, but careful breeding has made gold, white, black and spotted pets with fancy fins.
Carassius auratus is an East Asian cyprinid that was domesticated in China at least as early as the Song dynasty (960–1279). More than 125 breeds now exist, and fish released from ponds and tanks have formed wild populations far outside the native range, where they can harm lakes.
Photo: Kolforn (Kolforn) I'd appreciate if you could mail me (Kolforn@gmail.com) if you want to use this picture out of the Wikimedia project scope. This file is licensed under the Creative Commons Attributi, CC BY-SA 4.0, via Wikimedia Commons
Meet the goldfish
The goldfish is a fish that many people keep as a pet.
It swims in fish tanks and garden ponds. Goldfish can be gold, orange, white or black. Some have long, floaty fins.
The goldfish is a freshwater fish in the carp family. Many people keep it as a pet in tanks, bowls and garden ponds.
Goldfish are domesticated, which means people have bred them for a very long time. In China, people were keeping goldfish at least as early as the Song dynasty, which lasted from 960 to 1279. Since then they have bred more than 125 different kinds, from the plain comet to the celestial, whose eyes point up at the sky.
Carassius auratus belongs to the Cyprinidae, the carp family. Britannica dates its domestication in China to at least the Song dynasty (960–1279). By selecting and breeding unusual fish over centuries, keepers have produced more than 125 breeds, including the veiltail with its flowing three-lobed tail, the lionhead with a swollen hood on its head, and the celestial with upward-pointing eyes.
Its taxonomy is tangled. USGS notes that some authors treat the European Prussian carp as a subspecies of the goldfish and others treat the goldfish as a form of the crucian carp, and that goldfish often hybridize with common carp in the wild.
Quick facts
- Group
- Fish
- Length
- 15 to 20 cm
- Weight
- 100 to 300 g
- Lifespan in the wild
- 6 to 7 years
Where it lives
Wild goldfish come from China, Korea and Taiwan.
They live in calm rivers, lakes and ponds. Pet goldfish now live in homes all over the world.
The goldfish's wild home is East Asia. The IUCN lists China, Korea and Taiwan as its native range. There it lives in slow or still fresh water: ponds, lakes, marshes and quiet rivers.
Today people keep goldfish far from East Asia. Some have escaped or been let go, and the IUCN lists wild goldfish living in lakes and streams on every continent except Antarctica, including much of the United States. Those wild groups were not there before people brought them.
The IUCN global assessment lists the native range as China, Hong Kong, North and South Korea and Taiwan, and records introduced wild populations in more than 50 other countries and territories across every inhabited continent. Animal Diversity Web describes its habitat as slow-moving or still fresh water, from rivers and lakes to marshes, bogs and swamps.
USGS says the goldfish is thought to be the first foreign fish brought to North America, with the first recorded releases in the late 1600s. A 1984 review cited by USGS found it had been taken in the wild in every US state except Alaska, though some of those records may be repeated releases rather than breeding populations.
Continents
Where can you find this animal?
- Kept by people · Countries and seas named by a scientific source
- Lives here naturally · Countries and seas named by a scientific source
- Sightings recorded · Records of wild sightings (GBIF)
Kept by people · Countries and seas named by a scientific source
Goldfish are domesticated pets kept in tanks and ponds far beyond East Asia. This is not a wild range. Escaped and released goldfish also live wild in lakes and streams on every continent except Antarctica (IUCN).
Places: Asia, Europe, North America, South America, Africa and Australia and Oceania.
Source: iucn-red-list · checked October 2026
Lives here naturally · Countries and seas named by a scientific source
The wild goldfish's native home: slow and still fresh waters of East Asia in China (including Hong Kong), North and South Korea and Taiwan, as listed by the IUCN. Hong Kong is too small to show on this map.
Places: China, North Korea, South Korea and Taiwan.
Source: iucn-red-list · checked October 2026
Sightings recorded · Records of wild sightings (GBIF)
Counts of GBIF records of wild observations (human and machine) and preserved specimens. Records include introduced populations, vagrants, escaped or released animals and misidentifications, so a country with records is not necessarily part of the native range.
Wild sightings have been recorded in South Korea, Australia, United States, Ukraine, Japan, New Zealand, Germany, France and 87 more places.
Source: gbif · checked October 2026
Range maps show where scientists say an animal lives, often country by country. An animal may live in only part of a country shown, and sightings records can include animals that wandered far from home.
What it eats
Goldfish eat plants and tiny animals.
In a pond they nibble water plants, insects and little shrimp. Pet goldfish eat fish flakes and even peas.
Goldfish are omnivores: they eat both plants and animals. In the wild they search through water plants and along the sandy bottom for insects, tiny shrimp-like animals, worms, eggs and plants.
They have no teeth in their jaws. Instead they crush food with teeth far back in the throat. Pet goldfish are usually fed fish flakes, and keepers sometimes give them small vegetables such as peas.
Goldfish are opportunistic, bottom-foraging omnivores. Animal Diversity Web summarizes a study of a pond in Quebec where vegetation made up 45 percent of the diet, insects such as midges and mosquitoes 21 percent and small crustaceans 4 percent; worms and detritus were also eaten.
Like the rest of its order, the Cypriniformes, the goldfish has a toothless mouth (Britannica); the Minnesota DNR describes how it crushes food with pharyngeal teeth in the throat. Rooting through the bottom for food stirs up sediment, which is one reason wild goldfish can muddy lakes.
Did you know?
Wild goldfish are not gold. They are greenish-brown.
Wild goldfish are greenish-brown or gray. When pet goldfish are released, their babies usually turn out olive green.
USGS notes that offspring of brightly colored released goldfish are typically olive green, partly because predators pick off the bright ones.
A goldfish up close
Goldfish have big eyes and shiny scales.
They have no whiskers on their mouths. A tall fin stands up on the back. A wide tail pushes them along.
A goldfish has a stocky body covered in smooth scales, relatively large eyes and no scales on its head. Unlike its cousin the common carp, it has no whiskers, called barbels, around its mouth.
Its eyes are special. Goldfish can see four kinds of color: red, green, blue and ultraviolet, a color people cannot see. Along each side runs the lateral line, a row of sense organs that feels ripples and movement in the water.
USGS describes a stocky body with 25 to 31 scales along the lateral line, a long dorsal fin of 15 to 21 rays, and a stiff, saw-edged spine at the front of the dorsal and anal fins that separates it from other Asian cyprinids. It lacks the mouth barbels of the common carp.
Animal Diversity Web reports that goldfish are tetrachromats with cones sensitive to red, green, blue and ultraviolet light. The lateral line detects water movement, and the inner ear is coupled to the gas bladder, giving the fish sensitive hearing up to about 2 to 3 kilohertz.
From egg to adult
A goldfish starts as a tiny, sticky egg.
The eggs stick to water plants. After about a week, baby fish hatch. Baby goldfish are dark. Their bright color comes later.
Goldfish spawn in spring or summer. A female lays thousands of tiny eggs, each only about 1.2 to 1.5 millimeters across, and the males fertilize them in the water. The eggs stick to water plants.
After 2 to 9 days the babies, called fry, hatch at about 4.5 millimeters long. Goldfish parents do not look after their young. Baby goldfish are dark at first, and their gold color appears when they are two or three months old.
Spawning happens in spring or summer. Britannica notes that colors brighten and males may grow pinhead-sized bumps called tubercles on the gill covers and fins. Animal Diversity Web reports that a female usually releases 2,000 to 4,000 adhesive eggs at a time, fertilization is external, and several males may fertilize one female's eggs.
Eggs hatch in 2 to 9 days into larvae about 4.5 millimeters long. There is no parental care, and adults will eat eggs and young. Fry are dark and lose that pigment at two to three months; ADW gives sexual maturity at three to four years.
Life in a shoal
Goldfish like to swim together in groups.
They are gentle with each other. Goldfish can live in cold water, and in winter they slow down.
Goldfish are social fish. In the wild they swim in groups of a dozen or more, and sometimes several thousand. They are not aggressive with each other and do not guard a territory.
Goldfish are tough. They can cope with muddy water, changing temperatures and water with little oxygen, where many other fish would struggle. When the water gets colder than about 10 degrees Celsius in winter, they become much less active until spring.
Goldfish form shoals and, according to Animal Diversity Web, do not form social hierarchies or defend territories; they are most active around dusk and dawn. The Minnesota DNR reports groups of a dozen to several thousand fish in the wild.
Their tolerance is remarkable: turbid water, wide temperature swings, low dissolved oxygen and high ammonia. ADW reports that they become dormant in winter when water falls below about 10 °C, and can survive months of low oxygen near 2 °C. In one study, wild goldfish in Australia's Murray River moved about 0.3 kilometers a day on average, and one traveled 231 kilometers in a year.
Did you know?
Some pet goldfish have lived for 25 years.
Most goldfish live 6 or 7 years, but pet goldfish have been known to live 25 years.
USGS gives a typical lifespan of 6 to 7 years, with reports of up to 30 years; Britannica notes pets known to live 25 years.
Caring for goldfish and nature
Goldfish are not in danger.
But a pet goldfish should never be let go in a pond or river. It can harm the fish and plants that live there.
The IUCN lists the goldfish as Least Concern, so it is not in danger of dying out. The bigger problem is goldfish living where they do not belong.
When pet goldfish are let go into lakes, they can multiply into hundreds or thousands. They stir up mud while they feed, which clouds the water and harms water plants and native fish. If you can no longer keep a goldfish, never release it. Ask a pet shop or a fish club to help find it a new home.
The IUCN global assessment (assessed 2010, published 2013) lists the goldfish as Least Concern with an unknown population trend, and flags the assessment as needing an update.
Its conservation story is mostly about introductions. The Minnesota DNR, which regulates goldfish as an invasive species, says large wild populations can outcompete native fish, raise turbidity by stirring up sediment, reduce aquatic vegetation and carry fish diseases. Britannica notes that goldfish living wild revert to their natural color, and USGS reports that the surviving young of brightly colored released fish are typically olive green, partly because predators take the bright ones. The advice is simple: never release a goldfish; return it to a retailer or rehome it with another keeper.
Did you know?
Goldfish can see colors that people cannot see.
Goldfish see four kinds of color, including ultraviolet, which is invisible to people.
Goldfish are tetrachromats: their cones respond to red, green, blue and ultraviolet light.
Amazing facts
-
Goldfish can see colors that people cannot see.
Goldfish see four kinds of color, including ultraviolet, which is invisible to people.
Goldfish are tetrachromats: their cones respond to red, green, blue and ultraviolet light.
-
Wild goldfish are not gold. They are greenish-brown.
Wild goldfish are greenish-brown or gray. When pet goldfish are released, their babies usually turn out olive green.
USGS notes that offspring of brightly colored released goldfish are typically olive green, partly because predators pick off the bright ones.
-
Goldfish have teeth in their throats, not in their mouths.
Goldfish have no teeth in their jaws. They crush food with teeth far back in the throat.
Goldfish crush food with pharyngeal teeth, a cyprinid trait, rather than teeth in the jaws.
-
Some pet goldfish have lived for 25 years.
Most goldfish live 6 or 7 years, but pet goldfish have been known to live 25 years.
USGS gives a typical lifespan of 6 to 7 years, with reports of up to 30 years; Britannica notes pets known to live 25 years.
Words to know
- domesticated
- bred and kept by people for a very long time
- omnivore
- an animal that eats both plants and animals
- barbel
- a whisker-like feeler near a fish's mouth
- lateral line
- a row of sense organs along a fish's side that feels movement in the water
- fry
- baby fish that have just hatched
- invasive species
- a living thing that people moved to a new place, where it causes harm
Discovery challenge
-
Where did people first keep goldfish?
In which country did people first keep goldfish as pets?
In which country was the goldfish domesticated?
- China
- Brazil
- Australia
Show the answer
China
People in China kept goldfish long, long ago.
People in China were keeping goldfish at least as early as the Song dynasty (960 to 1279).
Britannica dates domestication in China to at least the Song dynasty (960–1279).
-
What color is a wild goldfish?
What color are goldfish that live in the wild?
What color do wild goldfish, and the offspring of released pets, usually have?
- Bright gold
- Greenish-brown or gray
- Bright blue
Show the answer
Greenish-brown or gray
Wild goldfish are greenish-brown. That helps them hide.
Wild goldfish are greenish-brown or gray. The bright colors come from breeding by people.
The natural color is greenish-brown or gray; USGS notes released fish usually produce olive-green young.
-
What do goldfish eat?
What do goldfish eat in the wild?
Which best describes the goldfish's natural diet?
- Only meat
- Plants and small animals
- Only sunlight
Show the answer
Plants and small animals
Goldfish eat water plants and tiny animals.
Goldfish are omnivores. They eat water plants, insects, tiny shrimp-like animals and worms.
They are opportunistic omnivores; in one pond study, plants were 45 percent of the diet and insects 21 percent.
-
What should you do with a pet goldfish you can't keep?
What is the right thing to do with a goldfish you can no longer care for?
What is the responsible choice for an unwanted pet goldfish?
- Let it go in a lake
- Find it a new home
- Put it in the sea
Show the answer
Find it a new home
Find it a new home. Goldfish in lakes can harm other animals.
A pet shop or fish club can help find it a new home. Released goldfish can muddy lakes and harm native fish.
Rehoming or returning it to a retailer avoids starting an invasive population; the Minnesota DNR asks owners never to release goldfish.
Places where you might see it
Experiments to try
- Watch What If? Lab What if you never blinked? You blink about 15 times a minute, mostly without noticing. Each blink spreads a thin layer of tears across your eyes to keep them moist and wash away dust. Imagine never blinking again, then discover what tears do, why eyes feel dry, and how fish and snakes manage with no eyelids that close.
- Watch What If? Lab What if you had gills? Fish don't breathe water itself: their gills take tiny amounts of oxygen gas out of the water. Air is about one fifth oxygen, but water holds only a few oxygen molecules in every million. Imagine growing gills, and find out how fish, and the smiling axolotl, get enough oxygen.
Explore next
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Watch
3D
Animal
Common carp
The common carp is a large, sturdy fish with big scales and little whisker-like barbels by its mouth. It comes from rivers and lakes of Europe and Central Asia, but people have carried it to every continent except Antarctica, where it can muddy the water and harm water plants. Koi are a colorful kind of carp.
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Watch
Country
China
China is the largest country in Asia, almost as big as all of Europe. The land steps down from the high, cold Plateau of Tibet in the west to plains and coasts in the east, and about 1.4 billion people live there, along with giant pandas in the mountains of south-central China.
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Watch
3D
Animal
Guppy
The guppy is a small freshwater fish from northeastern South America and nearby Caribbean islands such as Trinidad. Males are smaller and brightly colored; females are larger and plainer. Guppies give birth to live young, and they are one of the most popular aquarium fish in the world.
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Watch
3D
Animal
Siamese fighting fish
The Siamese fighting fish, often called the betta, is a small freshwater fish from shallow, warm waters in Thailand. It can breathe air with a special organ, and males build nests of bubbles for their eggs. People have bred bettas for many centuries, giving pet bettas their bright colors and long fins.
- Watch What If? Lab What if you never blinked? You blink about 15 times a minute, mostly without noticing. Each blink spreads a thin layer of tears across your eyes to keep them moist and wash away dust. Imagine never blinking again, then discover what tears do, why eyes feel dry, and how fish and snakes manage with no eyelids that close.
- Watch What If? Lab What if you had gills? Fish don't breathe water itself: their gills take tiny amounts of oxygen gas out of the water. Air is about one fifth oxygen, but water holds only a few oxygen molecules in every million. Imagine growing gills, and find out how fish, and the smiling axolotl, get enough oxygen.
-
Watch
Animal
Alligator gar
The alligator gar is one of the largest freshwater fish in North America. It has a broad snout lined with teeth, armor-like scales, and a swim bladder that works like a lung, so it can gulp air in warm, still water. It lives in the big rivers, swamps and bayous of the southern United States, Mexico and Central America.
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Watch
Animal
Arapaima
The arapaima is one of the biggest freshwater fish in the world, longer than a grown-up is tall. It lives in the warm, slow rivers and flooded lakes of the Amazon, and it must swim up to the surface to gulp air every few minutes.
For parents & teachers
What children will learn
- Explain what it means for an animal to be domesticated, using the goldfish as an example.
- Describe the goldfish's main body parts and senses, including its ultraviolet vision and lateral line.
- Describe the goldfish life cycle from sticky egg to adult.
- Understand why pet fish should never be released into the wild.
Recommended ages: 3 to 17 · About 12 minutes
Talk about it
- Why do you think wild goldfish are greenish-brown and not bright gold?
- How did people end up with so many kinds of goldfish?
- What could you do if a friend could not keep their goldfish anymore?
Try at home or in class
- Measure your hand from wrist to fingertip and compare it with a typical goldfish of 15 to 20 centimeters.
- If you keep a goldfish, watch it for five minutes and draw where its fins are and how each one moves.
Key vocabulary: domesticated, omnivore, barbel, lateral line, fry, invasive species
Where these facts come from
- The IUCN Red List of Threatened Species , International Union for Conservation of Nature (IUCN terms of use (no redistribution of Red List data or range maps))
- GBIF Backbone Taxonomy and GBIF Occurrence Search , Global Biodiversity Information Facility (CC0 1.0 (backbone); occurrence counts are facts derived from records under CC0, CC BY and CC BY-NC)
- Carassius auratus (Goldfish), global assessment , IUCN Red List of Threatened Species
- Goldfish (Carassius auratus) species profile , U.S. Geological Survey, Nonindigenous Aquatic Species
- Carassius auratus (goldfish) , Animal Diversity Web, University of Michigan Museum of Zoology
- Goldfish , Encyclopaedia Britannica
- Cypriniformes , Encyclopaedia Britannica
- Goldfish (Carassius auratus) , Minnesota Department of Natural Resources
- Wikidata , Wikimedia Foundation (CC0 1.0)
- Wikimedia Commons , Wikimedia Foundation (Per file: Public domain, CC0, CC BY or CC BY-SA only (credited on each page))
Checked, not yet human-reviewed. Last updated October 28, 2026. Spotted a mistake? Tell us.
Picture and 3D model credits
- Photo: Kolforn (Kolforn) I'd appreciate if you could mail me (Kolforn@gmail.com) if you want to use this picture out of the Wikimedia project scope. This file is licensed under the Creative Commons Attributi, CC BY-SA 4.0, via Wikimedia Commons · source · license
- Photo: Jiaqian AirplaneFan, CC BY 3.0, via Wikimedia Commons · source · license
- 3D model: Dyson, CC BY-SA 4.0 (ShareAlike: changed versions share under the same license), via Sketchfab · source · license