What the chart actually is
The Bristol stool form scale is a seven-point scale for describing stool by shape and consistency alone. It was developed at the Bristol Royal Infirmary and published in 1997 by S. J. Lewis and K. W. Heaton in the Scandinavian Journal of Gastroenterology, whose finding matters for anyone using the chart: stool form tracks how fast food is passing through the gut — the firmer the type, the slower the transit. That is why form, not colour or smell, is the thing worth logging.
The scale earned its place in clinics because it solves a communication problem. “How have your bowels been?” is a hard question to answer from memory, in words that mean the same thing to both people. A number from 1 to 7 does that job, which is why the chart hangs in hospital wards and sits in intake forms.
It is also taken seriously as a record. When one UK hospital ward made the chart part of routine nursing documentation — a small quality-improvement project over 30 patients — daily documentation of bowel movements rose from 27% to 73%, and correct chart use from 57% to 87% (Yaseen & Abuelas, Cureus, 2026). The numbers say nothing about any individual’s gut; they say that when a chart is at hand, people actually log, and the log is what clinicians act on.
How to read your own seven numbers
Group the scale into three bands and the month becomes readable:
- Types 1–2 — hard and lumpy. Food is moving slowly; the usual first suspects are too little water and too little fibre.
- Types 3–4 — formed and easy to pass. The typical middle most days land in; the shaded band on the chart above marks it.
- Types 5–7 — soft, mushy, watery. Transit is fast; a day or two after unfamiliar food or a stomach bug is ordinary, a fortnight of it is a reason to ask someone.
The summary line deliberately reports the share of entries in the typical zone rather than a score or a grade. A day at type 6 after a suspicious takeaway is your gut doing its job; the thing worth noticing is a band that never appears, or a slow drift from one band to another over weeks.
What a log gives you that memory does not
Everyone’s answer to “how has it been?” is a guess weighted towards the last two days. A tap-per-visit log removes the guesswork and shows three things nothing else will: the pattern (which band your normal actually is), the changes (what happened after the new diet, the new medicine, the stressful month), and the record (a page you can hand over). For a doctor deciding whether to test, treat or wait, a dated 30-day table is a different artefact from “I think it’s been a bit loose lately” — which is the whole reason wards keep bowel charts.
That is also the honest limit of the tool. It records what you tap; it does not examine anything, and it cannot tell you why a pattern looks the way it does. Blood in the stool, a persistent change, pain or unexplained weight loss belong with a clinician, immediately, printed log in hand — not with another week of logging.
Questions
Is my log uploaded anywhere?
No. Entries are saved in your own browser storage on this device — the same mechanism that remembers text you type into a form. There is no account, no sync, and no request ever carries a logged entry off the page. The export button gives you the raw data as a file you control, and Clear all deletes everything at once.
What are types 3 and 4?
The middle of the scale and the most common day-to-day result: a formed stool that passes easily, either with surface cracks (type 3) or smooth (type 4). Health services such as the Cleveland Clinic describe types 1–2 as leaning towards constipation and types 5–7 as loose or fast. One entry outside the middle is normal for almost everyone; the point of a log is the pattern, not the single day.
How long should I log before it means anything?
Weeks, not days. Stool form reacts to hydration, fibre, stress, sleep and medicines, so a single odd day usually says more about yesterday than about your gut. The chart and the summary here read a 30-day window for exactly that reason — long enough for a real pattern, short enough to finish.
Is this medical advice?
No. The Bristol scale is a communication aid: it lets you and a clinician describe the same thing with the same words. It does not diagnose anything. See a doctor about blood in the stool, a change that persists for weeks, pain, or unexplained weight loss — and take the printed summary along; a dated record is considerably harder to argue with than a memory.
What is poop-maxxing?
A 2026 trend — covered by NBC News under the headline “Poop-maxxing: how a 30-year-old chart became a hot gut health trend” — of young people tracking gut health with this exact chart. The reasonable version of the trend is what this page does: notice the pattern, adjust fibre and water, and bring the month to a doctor when something is off. The unreasonable version, chasing a “perfect” daily score, is not something a chart can give you.
Can I print the log for my doctor?
Yes — the Print 30-day summary button produces a dated table of every entry in the window: when, type, form, and your note. That is deliberately the same shape hospitals use for bowel records, because it is the form a nurse or doctor can read at a glance.