One minute, Dan's voice sounds normal. The next minute, he can barely get through a sentence without his voice sounding like it's out of control: high one minute, low the next, then high again. It's not a cold or a sore throat. In fact, everything feels normal — but nothing sounds right.

Dan's voice is changing. It's one of the many developments that happen to both girls and guys when they reach puberty. A guy's voice gets way deeper than a girl's, though.

What Causes My Voice to Change?

At puberty, guys' bodies begin producing a lot of the hormone testosterone (pronounced: tes-TAHS-tuh-rone), which causes changes in several parts of the body, including the voice. For starters, a guy's larynx (pronounced: LAR-inks), also known as the voice box, grows bigger.

The larynx, which is located in the throat at the top of the trachea (pronounced: TRAY-kee-ah) or windpipe, is like a hollow tube about 2 inches (5 centimeters) high. The larynx is responsible for creating the sound of your voice.

Stretched across your larynx are two muscles, your vocal cords, which are kind of like rubber bands. When you breathe, your vocal cords relax against the walls of the larynx and completely open to allow air to get in and out of your lungs. When you speak, though, your vocal cords close together by stretching across the larynx. Air from your lungs is then forced out between your vocal cords, causing them to vibrate and produce the tone of your voice.

When you lower your voice, your vocal cords are relaxed and more floppy. When you make your voice higher, your vocal cords tighten. (You can notice this difference in how they feel as you adjust your speech.)

As your larynx grows, your vocal cords grow longer and thicker. Also, your facial bones begin to grow. Cavities in the sinuses, the nose, and the back of the throat grow bigger, creating more space in the face that gives your voice more room to echo. All of these factors cause your voice to get deeper.

Think of a guitar. When a thin string is plucked, it vibrates and produces a high-sounding tone. When a thicker string is plucked, it sounds much deeper when it vibrates. That's kind of what happens to your voice. Before your growth spurt, your larynx is relatively small and your vocal cords are relatively thin. So your voice is high and kid-like. But as bones, cartilage, and vocal cords grow, your voice starts to sound like an adult's.

Along with all the other changes in your body, you might notice that your throat area looks a little different. For guys, when the larynx grows bigger, it tilts to a different angle inside the neck. Part of it sticks out in the part of the neck at the front of the throat and forms the Adam's apple. For girls, the larynx also grows bigger but not as much as a guy's. That's why girls don't have Adam's apples.

Why Is My Voice So Hard to Control?

While your body is getting used to these changes, your voice can be difficult to control. A guy's voice "cracks" or "breaks" because his body is getting used to the changing size of his larynx. Fortunately, the cracking and breaking is only temporary. It usually lasts no longer than a few months. And even during that time, your voice won't crack every time you speak.

Some guys' voices might drop gradually, whereas others' might drop quickly. You may feel concerned, stressed, or embarrassed about the sound of your voice, but people usually understand — especially friends or brothers who've gone through it, too. Everyone goes through it, and once it happens, it takes a while to adjust to your larger larynx and the new sound of your voice.

When Will My Voice Change?

You may have noticed that some of your friends have cracking and breaking voices, some might already have deep voices, and some still have the same voice they've always had. Everyone's timetable is different, so some voices might start to change earlier and some might start a little later.

Generally, a guy's voice will start to change somewhere between the ages of 11 and 15 — although it can be earlier or later for some. It all depends on when a guy goes through puberty, and some normal guys enter puberty earlier or later than others.

How Deep Will My Voice Get?

How deep a guy's voice gets depends on his genes: The larger a guy's larynx, the thicker the vocal cords, and the bigger the resonating area, the deeper his voice will be.

Once your larynx has grown, your voice will be more stable and easier to control. But even then your voice hasn't finished developing! Even after the quick change that happens in your teens, your voice continues to develop. Although the squeaking and cracking stage doesn't last long, most guys' voices don't fully mature until they're in their twenties.

Reviewed by: Steven Dowshen, MD
Date reviewed: May 2013