Bristol stool chart

The Bristol stool scale sorts stools into 7 types by their shape and how firm they are, from separate hard lumps (type 1) to watery (type 7). Doctors and nurses often use it, because a number is easier to share than a description.

Harder

1. Type 1 · Separate hard lumps

   Hard pieces like nuts, each one separate. Often hard to pass.

2. Type 2 · Lumpy sausage

   Sausage-shaped, but made of lumps stuck together.

In between

3. Type 3 · Sausage with cracks

   Sausage-shaped with cracks on the surface.

4. Type 4 · Smooth, soft sausage

   Like a sausage or snake, smooth and soft.

5. Type 5 · Soft blobs, clear edges

   Soft pieces with clear-cut edges. Easy to pass.

Looser

6. Type 6 · Mushy, ragged pieces

   Fluffy, mushy pieces with ragged edges.

7. Type 7 · Watery, no solid pieces

   Entirely liquid, with no solid pieces.

Free chart from stoollog.com. The Bristol stool scale was developed at the Bristol Royal Infirmary (Lewis and Heaton, 1997).

How people use the chart

The chart gives you and your doctor the same words for what you saw. Writing down the type each time, with the date and time, shows how your stools change over days and weeks, which is hard to remember at an appointment.

Stools vary from person to person and from day to day. The chart describes shapes; it doesn't tell you what's normal for you. Talk to a doctor about any change that worries you.

Where the scale comes from

The scale was developed by Dr Ken Heaton and Dr Stephen Lewis at the Bristol Royal Infirmary in England and published in 1997. It is now used in clinics and research around the world.