What your stool color means

Pick the color closest to yours. Each guide explains common causes in plain language and the signs that mean you should see a doctor.

Black and tarry, red or maroon, or pale and white? Those can be urgent. Check the warning signs. In an emergency, call 911 or your local emergency number.

How worried should you be?

Many color changes come from food, dye or medicine and pass in a day or two. Published medical guidance treats three colors differently.

  • Usually normal

    Shades of brown. Green, orange, blue or purple after food, dye or supplements, if you feel well.

  • Keep an eye on it

    Greasy, pale yellow stool that floats, or any change lasting more than a few days with no clear cause.

  • Can be urgent

    Black and tarry, red or maroon blood, and pale, clay or white stool. These can mean bleeding or a blocked bile duct.

These groups are a general guide, not a diagnosis. If you are worried about any change, or you feel unwell, contact a clinician whatever the color.

Warning signs to know

These are signs that published medical guidance says need prompt or urgent care. The list is not complete, and ticking boxes cannot tell you whether you are ill. If you are worried, contact a clinician whatever you tick.

Warning signs

Why stool is brown, and why it changes

Stool gets its brown color from bile, a fluid your liver makes to digest fat. Bile starts out green-yellow. As it moves through your intestines, bacteria change it, and it turns brown. Many color changes come down to what you ate, how fast food moved through your gut, or how much bile reached your intestines.

Food dyes, leafy greens, beets, iron tablets and some medicines can all change stool color for a day or two. Those changes are common and usually harmless. A color that stays different for more than a few days, or one that comes with pain, fever, weight loss or blood, is worth checking with a clinician.

Questions to ask yourself before you call

  • What did I eat or take in the last two or three days? Foods with strong color or dye, new medicines and supplements are common causes. Tell your clinician about them.
  • Do I have other symptoms? Belly pain, fever, dizziness, yellow skin, vomiting or weight loss change the picture.
  • How long has it lasted? A single odd stool usually matters less than a color that stays for days.

About StoolColor

Each guide explains possible causes in plain language, describes signs that published medical guidance treats as urgent, and lists the sources it draws on. StoolColor is not written or reviewed by a doctor. It cannot diagnose anything and does not replace a clinician. Read more on the about page.