Do Identical Twins Have the Same Voice? Influencing Factors

It is often believed that identical twins will share identical physical features. However, this belief often overlooks the possibility of them also having the same speaking voice. To what extent does being a twin affect a child’s voice?

Do identical twins have the same voice?

Twins do not have the exact same voice. Though there are definitely factors that make identical twins sound very similar, their voices are still unique. Just like fingerprints, no two voices are exactly alike. They are impacted by more than just genetics, and that’s why you may be able to tell identical twins apart by their voices.

Knowing how voices develop is key to understanding why twin voices sound the way they do. Studying the voices of twins may even give us insight into how much genetics impact musical talent.

Voices of Identical Twins – Same or Different?

If you’re blindfolded and asked to tell which identical twin is speaking to you, you may have a very hard time figuring out the correct answer.

Identical twins share an almost exact genetic makeup, and this does impact how similar their voices are. Still, there are subtle differences.

Pitch & Inflection

Pitch is defined as the highness or lowness of a tone. We tend to use the term pitch when we are talking about changes in music or other sounds. 

Inflection is a change in the tone of a word to express something related to spoken language. For instance, the inflection of a voice changes when someone is asking a question as opposed to making a statement.

Speech Patterns

You may already know that identical twins are more likely to be speech delayed or struggle with speech impediments than singletons. This can affect their speech patterns or the way they say words.

Identical twins may also start speaking later than singletons, especially if they create their own language and simply communicate with each other. However, as twins do start speaking, telling them apart by their speech patterns may become easier.

Singing Voice

An interesting study is ongoing and should tell us more about twins, musical talent, and singing voices. Researchers want to determine how much singing talent is hereditary and how much can be taught. Identical twins are the perfect test subjects for this kind of experiment.

Even before the results of the study are published, twins Yolanda and Yasmin say their voices actually help them be less identical. Though they can both sing, they each recognize their distinct vocal strengths and how they make them sound different. 


When you have twins, it may feel like the volume is always turned up in life. How loud or quiet your kids’ voices are is determined by several things. Researchers found that biology, culture, personality, and pathology all affected whether someone ended up being a loud or quiet speaker. 

While twins definitely have biology in common and will more than likely be raised in the same culture, the other two components could result in one twin being louder than the other. Even identical twins don’t have identical personalities.

How Do Voices Develop?

Vocal cords develop in the womb at around 28 weeks. This helps ensure you hear those first cries as soon as your babies make their grand entrance. In fact, the main purpose of your children’s vocal cords when they are babies is to cry out for help when it’s needed. There’s a reason those sounds send a jolt right through you.

As twins age, their vocal physiology will as well. They will be able to do more with their voices than cry or yell, and they will start to learn words from those around them. 

Twins growing up in the same home will not always speak at the same time or in the same way. However, the combination of genetics and shared environment can make their experiences similar.

Since pathology also influences voice and speech, a twin who needed more medical care or spent longer in the neonatal intensive care unit could sound different than a twin sibling.

Factors That Affect Voice

Voices are affected by genetics. However, there are a host of other factors that influence how voices sound. 

Age plays a role in how voices sound. Kids hitting puberty undergo voice changes, especially males. As people age, their voices change due to the effects of aging on their vocal cords and surrounding tissues.

Smoking, drinking, or living in an area with high pollution will affect the sound of someone’s voice, as will their health.

How To Tell Twins Apart by Their Voices

A study showed that while it isn’t always easy to tell identical twins apart using only their voices, it is possible. Around 80 percent of study participants could when presented with two different twin voices.

Differences in pitch, speech patterns, and tone are all ways to determine which voice belongs to which identical twin. It’s true that twin voices are similar, so it will still require effort to pick on the small differences in the way they speak. 

Related Questions

Do All Twins Make Up Their Own Language?

Not every set of twins will have their own language, usually known as autonomous language. However, studies show that around 40 percent of twins do come up with their own language that doesn’t make sense to other people. Over time, they will usually abandon this language, but it does often exist in the early years.

Do Twins Usually Have the Same Intelligence?

Identical twins share genes, and studies have shown that they tend to have around the same intelligence levels. Though the environment a child grows up in can affect their intelligence, identical twins still prove that certain traits are majorly influenced by genes.

Fraternal twins don’t share as many genes as identical twins, and this is reflected in their intelligence differences.

Identical twins are naturally going to have many things in common, including their voices because they share the same genes. However, there are ways to tell them apart by paying attention to the minute details of each person.