The Bristol Stool Chart Explained

The Bristol Stool Chart sorts your poo into seven separate categories based on its shape and texture — ranging from hard lumps to complete liquid. Your GP or nurse might refer to this guide when talking through your bowel habits with you, as it helps everyone get straight to the point about what's going on in the loo.

The Bristol Stool Chart is a handy visual guide used by healthcare professionals to assess your poo. Originally developed in Bristol in the late 1990s, it classifies stool into seven types based on firmness and shape. If you're discussing digestive troubles with your doctor, using the chart makes it much easier to describe. You can also use it at home to keep track of any changes to your usual habits.

Why do your poos matter?

The shape, colour, and smell of your bowel movements are vital indicators of your overall health. They can quickly show if your digestive system isn't running smoothly:

  • Hard, lumpy stool usually points to dehydration or sluggish bowels.

  • Soft, runny or mushy poo often signals an upset stomach, infection, or food intolerance.

By categorising these textures, doctors can diagnose conditions like constipation, diarrhoea, and irritable bowel syndrome (IBS).

The 7 Bristol Stool Types

The chart helps you and your GP figure out what’s normal for you, what’s ideal, and what might need attention:

  • Type 1: Stool appears as separate hard lumps, difficult to pass

  • Type 2: Lumpy and firm. slightly harder to pass than normal

  • Type 3: Like a textured, soft sausage with minor cracks

  • Type 4: Long, smooth and easily passed. Ideal stool

  • Type 5: Small, soft, easily passed blobs with defined edges

  • Type 6: A fluffy piece with ragged edges indicating faster transit

  • Type 7: Entirely liquid consistency indicating rapid passage

What the types tell you

  • Types 1 and 2 suggest constipation. These are dry, hard, and painful to pass. They usually happen when food moves too slowly through your gut and loses too much water along the way.

  • Types 3 and 4 are ideal. They hold their shape well without being dry or hard, showing that your digestive tract is moving at a steady, healthy pace.

  • Types 5, 6, and 7 indicate diarrhoea. Soft, mushy, or completely liquid poos pass very quickly and can be hard to hold in. This happens when your bowels work too fast and don't absorb enough water.

Does it work for children?

Yes, though paediatricians often use a simplified version called the Modified Bristol Stool Form Scale. This version drops Types 3 and 5, leaving five clear categories that are easier for young children to recognise and point to on a chart during a check-up.

What should you do if your poo isn't ideal?

It’s completely normal to have the odd hard or runny poo now and then. What you eat, how much water or alcohol you drink, or a brief stomach bug can throw things off for a day or two.

However, if your poos are consistently abnormal, here is what you should consider:

  • For constipation (Types 1 & 2): Drink plenty of water, move around more, and boost your dietary fibre. If self-care doesn't help, you can speak to a pharmacist about an over-the-counter laxative. If you're relying on laxatives regularly, see your GP so they can check for underlying causes.

  • For diarrhoea (Types 5–7): Ongoing looseness can be caused by food intolerances or side effects from medication. Mild looseness (Type 5) might improve by adding more soluble fibre to your diet. If you have persistent, watery diarrhoea, book an appointment with your GP.

A note on talking about your gut: Bowel habits can feel uncomfortable to chat about, but doctors talk about poo every single day. The Bristol Stool Chart takes away the awkwardness — you can simply point to a number and let the chart do the explaining.