Bristol Stool Chart: The 7 Types and How to Use Them

The Bristol Stool Chart gives you seven pictures to compare against what’s in the toilet. Types 1 and 2 are hard, types 3 and 4 are the comfortable middle, and types 5 to 7 get looser until type 7 is liquid. Doctors use it so that “normal” and “a bit off” mean the same thing to both of you.

The seven types at a glance

Type	What it looks like	What it usually suggests
1	Separate hard lumps, like pebbles	Constipation
2	Sausage-shaped but hard and lumpy	Constipation
3	Sausage with cracks on the surface	Ideal
4	Smooth, soft, snake-like	Ideal
5	Soft blobs with clear-cut edges	Mild diarrhea
6	Fluffy, mushy pieces with ragged edges	Diarrhea
7	Watery, no solid pieces	Diarrhea

The descriptions follow Cleveland Clinic’s version of the chart. Continence Health Australia, formerly the Continence Foundation of Australia, groups the same scale more simply: 1 and 2 point to constipation, 3 and 4 are healthy and easy to pass, and 5 to 7 point to diarrhoea or urgency.

What shape says about speed, and where that stops

In a 1997 study, Stephen Lewis and Ken Heaton measured how long marker pellets took to pass through the gut in 66 volunteers, then, in most of them, sped things up with senna or slowed them down with loperamide. Stool form followed those changes more closely than how often people went.

Cleveland Clinic gives the plain version. Stool can turn into types 1 and 2 when it spends too long traveling through the intestines. Types 5 to 7 happen when the bowel moves too fast and doesn’t absorb enough water.

The link has limits. A 2010 multicenter study found a moderate correlation between stool form and transit in constipated adults, and none in healthy adults. Treat the type as a description of what you saw, not a measurement of your gut.

“How often” and “what shape” are also separate questions. NIDDK defines constipation as fewer than three bowel movements a week, or stools that are hard, dry or lumpy. Someone who goes every day but always passes type 1 pellets can still be constipated.

When you can’t tell which type it is

Sometimes stool looks like something between two pictures. A few habits keep your log readable:

• Pick the type it looks closest to. If you weren’t sure, say so in a note.
• If one movement starts firm and ends soft, write that down, for example “hard first, then loose”.
• Log each bowel movement separately instead of averaging the day.
• Note color, blood or mucus apart from the type. Shape and color answer different questions, and the stool color guide covers the shades.

A week in the log

Here is an invented example of what a week can show that a single day can’t:

Day	Types logged	Notes
Mon	4
Tue	4
Wed	2	Long drive, little water
Thu	2, 3
Fri	4
Sat	6, 5	Takeaway curry Friday night
Sun	4

Five days include a type 3 or 4. Wednesday, Thursday and Saturday also have types outside that range, and two of those days carry a note about what was going on. A note records context. It doesn’t prove the cause, but it gives you and a doctor something specific to ask about.

A log where type 6 or 7 shows up most days reads differently. That is worth showing a doctor even if you think food explains it.

When to see a doctor

Cleveland Clinic notes that an occasional hard or mushy stool is normal, since food, water, alcohol and stomach bugs all shift it. It says to see a doctor if you find you need stool softeners or laxatives often, or if very runny diarrhea goes on for a long time. Stools that are consistently unhealthy may call for changes to your habits, and in some cases medical treatment.

The NHS lists changes in poo that are not usual for you, such as softer poo, diarrhoea or constipation, as a reason to see a GP. It also gives faster routes:

• Call NHS 111 now if you have had diarrhoea for more than 7 days.
• Ask for an urgent GP appointment or contact NHS 111 if your poo is black or dark red, or you have bloody diarrhoea.
• Call 999 or go to A&E if you are bleeding non-stop from your bottom, or there is a lot of blood or large clots when you poo.

Outside the UK, contact a doctor or urgent care service promptly in the first two situations. If bleeding won’t stop, there is a lot of blood, or you see large blood clots, call your local emergency number or go to an emergency department right away. This article is general information, not medical advice.

How bellySignal helps

In bellySignal you tap the Bristol type that matches, then add stool color, blood or mucus, and a note about what was going on that day. Over a few weeks the log shows whether you mostly sit at 3 and 4 or keep drifting to one end, and you can export it to show a doctor instead of trying to remember.

Your diary is stored on your device, and no account is required. Selected health values, including stool type, symptoms and manually entered weight, are also sent to PostHog, which is enabled by default. The analytics switch controls PostHog only. Firebase Analytics receives usage events without those health values and remains active. Privacy policy.