Why Helium Makes Your Voice High

Breathing helium from a balloon makes your voice sound high and funny. This happens because helium is much lighter than air. Sound travels about three times faster in helium than in regular air. Your vocal cords vibrate the same way, but the faster sound changes how your voice resonates.

How It Works

Your vocal cords create sound by vibrating. The sound bounces around inside your throat and mouth. These spaces act like a musical instrument, adding certain tones to your voice. When helium replaces the air in your throat, sound moves faster. This changes which tones get boosted, making your voice sound higher and squeakier.

Safety Concerns

While breathing a little helium for fun might seem harmless, it can be dangerous. Helium pushes oxygen out of your lungs. Breathing too much helium can make you dizzy or even pass out because your brain is not getting enough oxygen. You should never breathe helium directly from a pressurized tank.

Fun Facts

• Sulfur hexafluoride is a gas that does the opposite of helium. It makes your voice sound deep and low.
• Helium is the second most common element in the universe but is fairly rare on Earth.
• Sound travels at about 3,050 feet per second in helium compared to about 1,125 feet per second in air.

Did You Know?

Helium does not actually change the pitch of your vocal cords. They still vibrate at the same frequency. What changes is the resonance, the way sound bounces around in your throat. It is similar to how different shaped instruments make different sounds!