The bladder stores urine until it’s time to pee, then contracts to help push the urine out of the body. It also signals your brain when it’s filling up so you know when to use the bathroom.

Quick Scoop

Your kidneys make urine, and the bladder acts like a temporary holding tank for it. As it fills, nerves in the bladder send signals that create the urge to urinate.

In Simple Terms

  • Stores urine. The bladder holds pee before release.
  • Helps you urinate. The bladder muscle tightens and the sphincters relax so urine can flow out.
  • Communicates fullness. Stretch sensors tell your brain when it’s getting full.

Typical Capacity

A healthy adult bladder usually holds about 500 to 700 mL of urine, though the urge to go often starts earlier, around 200 to 350 mL.

If you want, I can also explain how the bladder works with the kidneys and urethra in one short diagram-like overview.