How To Tell How Old A Betta Fish Is?

The average lifespan of a betta fish is two to three years, but this can vary depending on the care the fish receives.

One way to tell how old a betta fish is by its color. As betta fish age, their colors will fade. Another way to tell how old a betta fish is by its fins.

As betta fish age, their fins will become more ragged and less colorful.

How To Tell How Old A Betta Fish Is?

To identify the age of a betta fish, you must look at certain traits. Here are some indications you can use to determine the age of your betta fish.


Like any living animal, betta also grows old. Sometimes it will be easy for you to determine the age of juvenile betta by their size.

When they first hatch, they are likely to be so tiny that it will be difficult for you to see them.

The smallest one you could purchase at a specialty store is only 1/2 inch long.

These fish start taking prepared food at this age; you can grab them during this period.

Bettas males tend to be larger than females. Generally, after 4 months, it can be difficult to determine the betta’s age based on their size alone, so you should use the other techniques.

Besides, a female betta is generally fully grown at around 2 inches. However, some male bettas are up to two inches taller.

Nevertheless, this only helps up to 3 months from the day it’s born and can help establish the age of the young betta.


By very good-looking betta’s eyes, you will notice that they are delicate and highly detailed. In fact, bettas can also perceive every color we can see. They are much more susceptible to eye issues or infections as they age.

Bettas can frequently go through cataracts that cloud one of their eyes. A few cases can be remedied through simple water changes.

Nevertheless, old bettas may commonly have cloudy eyes due to poor vision that goes unnoticed until they suddenly start to worsen, without any apparent outward signs.

Scales and Fins

The fins and scales of older betta may surprise you, as the younger betta’s fins and scales have very little coloration. Young betta under two months typically has circular fins with a little coloring. The fins are also small.

With growing age their fins will slowly change color and become marked. However, after a subject reaches approximately 1 year of age and the scale becomes marked, you will see that the fin coloration starts to lessen. In addition, the scales will usually take on a dimmer look.

There another chance is the marble gene; this gene is surprisingly activated throughout a betta’s life and causes them to change colors at least once until the gene comes again.

As a result, bettas normally retreat to darker colors as time passes on; Color changes to brighter.

Stripes or Color

One can often see stripes usually seen two months of age simply since they have not fully grown their color.

While bettas can make these spots, they are called “stress stripes” and only appear if the betta is extremely stressed.

On the other hand, if you see vertical stripes, that means these are breeding stripes.

Young bettas can be seen wearing vertical stripes shortly after birth simply because their body colors have not yet fully developed.

These stripes are horizontal and thus make up part of an animal’s camouflage in the wild.

Bettas can turn these high spots red throughout their lives, but it is not a good indication when you see these patterns on an elderly or adult betta.

These spots are called golden stress marks and do not appear unless the fish is extremely stressed.

Final Words

It takes a good deal of knowledge to determine the exact age of a betta since you cannot tell such things unless they are a baby.

When developing a method of identifying bettas of a certain age, you can gauge their size and color.