Thanks for your question. Many people have questions about their testicles (or balls). Bottom line, it’s normal for one testicle to be slightly larger than the other. However, if it’s a big difference, it’s a good idea to see a healthcare provider.

Is it normal for testicles to be different sizes?

Like your hands or feet, it’s normal for one testicle to be slightly larger than the other. You may even notice that one hangs a little lower or a little more horizontal (or flatter) than the other.

However, if you notice a big difference, it’s a good idea to be seen by a healthcare provider.

What causes one testicle to be larger than another?

One of the most common reasons for a difference in size of testicles is puberty. It’s fairly common for one testicle to grow slightly faster than the other. By the end of puberty, they should be fairly similar.

Sometimes one testicle can feel bigger than the other and it has nothing to do with your testicles. In your scrotum (the sac that holds your testicles) that are also blood vessels and tubes (that help transport sperm). Some causes of swelling in that area are:

• Varicocele. This is a swelling of the veins in the scrotum. It typically causes a dull pain or heaviness.
• Hydrocele. This is a collection of fluid (or liquid) around the testicle. It’s usually painless, but sometimes can be associated with a dull pain or heaviness.
• Hernia. An inguinal hernia is a bulging of contents of the abdomen that goes through a weak part in the lower abdomen. This can cause bulging, swelling, or pain in the scrotum.

When should I get checked out by a healthcare provider?

You should see a healthcare provider if:

• It’s easy to tell that one testicle is bigger than the other
• You have pain

What will the healthcare provider do during the visit?

If you see a healthcare provider for concerns about your testicles:

• They will ask questions. They may ask you about your medical history, how you’ve progressed through puberty, medications, and symptoms you may be having. They will probably ask you about your sexual health (including whether you have sex or masturbate). It’s important to know that sexual health information is confidential in most places.
• They will do a physical exam including a testicular exam. It’s important to know that it’s your body and your choice, so you get to decide what parts of the exam are done. You can also ask for a chaperone (or extra support person) to be present during the exam, such as a nurse or trusted adult. A testicular exam can help your healthcare provider determine whether your testicles are normal, or whether you need more monitoring or testing. During the exam, they will have you stand and lower your underwear so that they can see whether your testicles and penis look healthy. Then they will palpate (or touch) your testicles to make sure they are similar in size, a normal size for your age and pubertal stage, and that they feel normal. If you are uncircumcised a healthcare provider will probably ask you to gently retract (or pull back) your foreskin to make sure your penis looks healthy. If the healthcare provider has concerns, they may ask you to cough or may have you lie down on an exam table and repeat parts of the exam.
• They may get testing. If everything looks normal on an exam your healthcare provider may not get any tests. If there are any concerns they may have you get an ultrasound (that takes images of your testicles), blood tests, or urine tests.