The Purina poop scale is a fecal scoring chart that rates stool on a 1 to 7 scale, from very hard and dry at one end to watery with no shape at the other. Firm, well-formed stool sits toward the low-middle of the range, and scores that drift toward either end are worth a closer look. The chart is a common tool in vet offices, and you can use the same idea at home to describe your cat's stool with one number.
What is the Purina poop scale?
Purina publishes fecal scoring charts for dogs and cats. Each score has a photo and a short description, and the aim is to replace vague words like "loose" or "a bit hard" with a shared reference. A vet who hears "a 5 for three days" knows what you mean without a long explanation.
The general idea works like this:
- Low scores describe hard, dry, crumbly stool.
- Middle scores describe firm to moist stool that keeps a log shape and is easy to pick up.
- High scores describe soft, shapeless stool, ending in liquid.
Exact score definitions and photos are on the chart itself, so use the current version from Purina or your vet rather than relying on a summary. Our own cat fecal score chart guide shows how to log scores over time.
How do you score your cat's stool?
- Scoop the stool when it is fresh, since it dries and hardens within hours.
- Compare it with the chart and pick the closest match. If it sits between two scores, note both.
- Write the date, the score and any notes on colour, mucus or blood.
- In a multi-cat home, note which cat you think it came from, or leave it blank if you are unsure.
Take a photo when you can. A picture with the date is often more useful to your vet than the score alone. Scores also depend on the scorer, so judge with the same light and the same chart each time.
What do the scores mean for your cat?
One unusual score means little. A trend means more. Three checks help you read the pattern:
- Duration. A single soft stool after a diet change is common. Several days in a row deserves a call to your vet.
- Direction. A slow drift toward harder stool can point to constipation or low water intake, and a drift toward softer stool can point to diet, stress or a gut problem.
- Company. Vomiting, low energy, poor appetite or blood alongside a stool change raises the urgency.
Call your vet if a cat has no stool for 48 hours, or if you see blood or black, tarry stool, whatever score it has. Read the Cornell guide to feline constipation and the VCA guide to diarrhea in cats for more on each end of the scale.
Why use a score instead of words?
Words like "loose", "mushy" or "runny" mean different things to different people. A number tied to a picture gives you and your vet the same reference. It also makes trends easy to read. "Mostly middle scores, then four higher scores in a row" is clearer than "she has been off lately."
A score works best as a shared shorthand for a change you can already see. It does not tell you the cause, and a normal score does not rule out a problem.
What can throw off a stool score?
- Time in the box. Stool dries out, so an old stool reads harder than it was.
- Litter type. Clumping litter can stick to soft stool and hide its true shape.
- Diet changes. A new food can shift stool for a few days without meaning illness.
- Multiple cats. A score without a cat attached is hard to use.
- Medication and supplements. Some change stool colour or firmness, so mention them to your vet.
Score the same way each time: same light, same chart, fresh stool. If you are unsure, write both scores and add a photo.
How does a 1 to 7 score compare with LitterLens stool categories?
LitterLens does not produce a 1 to 7 score. Its stool image analysis sorts each stool into three shape groups: hard, soft or watery. It also labels colour as black-tarry, red, grey, green or orange-yellow. The groups are coarser than a seven-point chart, and they cover the same ground in plain terms.
| Fecal score idea | LitterLens shape group |
|---|---|
| Low scores: hard, dry, crumbly | Hard |
| Middle scores: firm and well-formed | No abnormal shape group applies |
| Higher scores: soft, shapeless | Soft |
| Top score: liquid | Watery |
The comparison is approximate, because the two systems use different definitions and neither replaces a vet's exam. The scale requires you to judge each stool by eye and record it. The camera records every visit for you, which helps when you cannot get to the box in time or when several cats share it. For shared boxes, the multi-cat health monitoring collection lists the bundles.
What does the camera add to a manual score?
Manual scoring works well for one cat and one scooper. Its weak point is consistency: you score what you happen to see. LitterLens keeps a log per cat with visit count, time in the box and stool images, and it compares each cat against its own baseline, built from about 7 days of visits and steadier after about 30 days.
It does not diagnose anything. Alerts for abnormal stool and data need the Care+ subscription, while live view, recording and visit data are free. See the how LitterLens works page for the tracking details, and browse the cat health monitoring collection for setups. The camera does not suit automatic or self-cleaning boxes, needs a flat surface and works best with a box larger than 50 by 38 cm.
What does a simple score log look like?
A log can be short. One line per day is enough: date, score, colour, and a note. For example, a week might read "Mon 3, brown. Tue 3, brown. Wed 5, brown, new treat. Thu 5. Fri 6, lethargic." A vet reading that sees a clear drift, a likely trigger and a worsening sign, and can act on it.
Keep the log in one place, such as a notes app, and add the cat's name if you have more than one. After a few weeks you will know what your cat's usual scores are. Your cat's usual range is a better reference than the chart alone, since a cat that always sits at the firmer end of normal is a different case from one that suddenly moves there.
What should you take to the vet?
Bring the dated scores or photos, the colour notes, and any change in diet or medication. Say how long the change has lasted and whether your cat is eating and drinking normally. Our article on sharing pet health data with your vet covers how to package it, and the healthy cat stool guide shows what a good score looks like in practice.
FAQs About the Purina Poop Scale for Cats
What is a good score on the Purina fecal scale?
Firm, well-formed stool near the low-middle of the scale. Check the current chart for exact definitions, and ask your vet what is normal for your cat.
Is the scale the same for cats and dogs?
The idea is the same. Purina publishes separate charts for each species, so use the cat chart for cats.
Does LitterLens give a Purina score?
No. It sorts stool into hard, soft or watery, and labels colour. Your vet can still work from its images.
When should I call the vet about a stool score?
Call if there is no stool for 48 hours, or if you see blood or black, tarry stool. Also call if abnormal scores last several days or come with vomiting or low energy.
