According to National Geographic, goldfish are usually around 7 to 16.1 inches long and weigh 0.2 to 0.6 pounds, but can top 5 pounds in the wild.

How big can common goldfish get?

When they are kept as pets in small fish tanks and aquariums, goldfish tend to stay about 1-2 inches long and never grow larger than 6 inches (15 centimeters), according to the DEC. However, in the wild, goldfish often reach 12 to 14 inches (30 to 35 cm) in length.

How long does it take for goldfish to grow full size?

So, How Quickly Do Goldfish Grow? If you're wondering how long it's going to take your goldfish to grow, then the answer is: Around one inch per year. That's right if you have a goldfish then you can expect them to grow an inch every 365 days. However, during their first few months of life, they'll grow a lot faster.