When a surgeon asks whether a patient with cirrhosis can safely undergo an operation, the answer rarely comes from a single lab value. It comes from a composite picture of how well the liver is still doing its job, and for more than fifty years that picture has been the Child-Pugh score.

The calculator above turns five clinical inputs into that picture. You enter total bilirubin, serum albumin, and INR, then grade ascites and hepatic encephalopathy, and it returns the total score from 5 to 15 with the verdict that matters most: Class A, B, or C.

This guide walks through each criterion, explains how the total becomes a class, and puts the real-world meaning of each class into context: operative risk, survival, and where the score is actually used. It is strictly informational and is not medical advice.

What Does the Child-Pugh Calculator Do?

You supply the five Child-Pugh criteria: three laboratory values and two clinical grades. The calculator assigns 1, 2, or 3 points to each, adds them, and delivers the classification verdict.

The headline answer names the class and the total points, for example Child-Pugh Class B with 9 points. Below it, labeled rows show the points each criterion contributed, so you can see exactly what pushed the score up or kept it down.

The verdict panel then lists all three classes with their operative risk context: Class A carries roughly 10 percent operative mortality, Class B roughly 30 percent, and Class C roughly 80 percent, with your class highlighted. A plain-language paragraph explains what the verdict means in practice.

How to Use the Child-Pugh Calculator

Enter the three lab values in their stated units: total bilirubin in milligrams per deciliter, serum albumin in grams per deciliter, and the INR as a plain number. The hint under each field shows the point bands, so you can anticipate the scoring as you type.

Grade ascites as none, slight, or moderate to severe, and hepatic encephalopathy as none, mild (Grade 1 to 2), or severe (Grade 3 to 4). Be honest with the two subjective grades; they carry the same weight as the labs.

Press Calculate and read the verdict first, then the rows. If you are a student or a clinician double-checking a chart, the per-criterion rows make it easy to audit the arithmetic.

The Five Criteria Behind the Score

Bilirubin measures the liver's ability to clear waste: below 2 mg per dL scores 1 point, 2 to 3 scores 2, and above 3 scores 3. Rising bilirubin with deepening jaundice is one of the most visible signs of a failing liver.

Albumin measures the liver's synthetic function, its ability to manufacture proteins: above 3.5 g per dL scores 1, 2.8 to 3.5 scores 2, and below 2.8 scores 3. Low albumin also contributes to swelling and fluid shifts.

INR measures clotting, another synthetic job of the liver: below 1.7 scores 1, 1.7 to 2.3 scores 2, and above 2.3 scores 3. A climbing INR means the liver is no longer making clotting factors reliably.

Ascites, the accumulation of fluid in the abdomen, and encephalopathy, the confusion caused by toxins the liver fails to clear, are graded clinically at 1, 2, or 3 points. Together the five criteria cover clearance, synthesis, and the body's visible distress signals.

From Total Score to Class: A, B, or C

The five criteria give a minimum of 5 and a maximum of 15 points. Totals of 5 to 6 place the patient in Class A, well-compensated liver function. Totals of 7 to 9 give Class B, significant functional compromise. Totals of 10 to 15 give Class C, decompensated disease.

The class boundaries are where small differences matter most. A total of 6 is Class A while 7 is Class B, and a single 2-point criterion, like mild encephalopathy or slight ascites, can be the difference.

The formula is:

Child-Pugh score = bilirubin points + albumin points + INR points + ascites points + encephalopathy points

Each term is 1, 2, or 3, and the class follows from the sum: 5 to 6 is A, 7 to 9 is B, 10 to 15 is C.

What Each Class Means for Surgery

Class A means the liver is compensating well. Elective surgery is generally considered reasonable risk, with operative mortality around 10 percent in classic studies, though the specific operation and the patient's other conditions still matter.

Class B means significant compromise. Operative mortality rises to roughly 30 percent, so surgical teams weigh the urgency of the operation heavily, optimize what can be optimized, and sometimes choose less invasive approaches.

Class C means decompensation. With operative mortality around 80 percent, elective surgery is usually avoided entirely; care shifts to medical management of the liver disease and, where appropriate, transplant evaluation.

These figures come from the surgical literature that made the score famous, and they describe populations, not individuals. Your surgeon and hepatologist interpret them alongside everything else they know about the patient.

Worked Example: A Textbook Class A Case

Consider a patient with bilirubin 1.2 mg per dL, albumin 3.8 g per dL, INR 1.2, no ascites, and no encephalopathy.

Score each criterion: bilirubin below 2 gives 1 point, albumin above 3.5 gives 1 point, INR below 1.7 gives 1 point, and the two absent clinical findings give 1 point each. The total is 5.

Five points falls in the 5 to 6 range, so the verdict is Class A. Operative mortality around 10 percent and one-year survival near 100 percent describe this band in the classic literature.

Answer: Class A, well-compensated. Elective surgery is generally considered reasonable risk, pending the surgical team's full assessment.

Worked Example: A Middle-of-the-Road Class B Case

Now take bilirubin 2.5 mg per dL, albumin 3.1 g per dL, INR 1.9, slight ascites, and no encephalopathy.

Bilirubin in the 2 to 3 band gives 2 points. Albumin in the 2.8 to 3.5 band gives 2 points. INR in the 1.7 to 2.3 band gives 2 points. Slight ascites gives 2 points and absent encephalopathy gives 1 point.

The total is 9, squarely in the 7 to 9 range for Class B. This band carries roughly 30 percent operative mortality and about 80 percent one-year survival.

Answer: Class B, significant compromise. The surgical team would think hard about whether the operation can wait or be done less invasively.

Worked Example: A Decompensated Class C Case

Consider bilirubin 4.0 mg per dL, albumin 2.6 g per dL, INR 2.6, moderate to severe ascites, and severe encephalopathy.

Every criterion hits the worst band: bilirubin above 3 gives 3 points, albumin below 2.8 gives 3, INR above 2.3 gives 3, and the two severe clinical grades give 3 each. The total is 15, the maximum.

Fifteen points is Class C, the decompensated band, where operative mortality approaches 80 percent and one-year survival is roughly 45 percent.

Answer: Class C, decompensated. Elective surgery is generally off the table; the focus is medical management and transplant evaluation where appropriate.

Worked Example: A Borderline Score That Changes the Verdict

Finally, take bilirubin 1.9 mg per dL, albumin 3.5 g per dL, INR 1.6, no ascites, and mild encephalopathy.

Bilirubin below 2 gives 1 point. Albumin at exactly 3.5 is not above 3.5, so it falls in the 2.8 to 3.5 band for 2 points. INR below 1.7 gives 1 point, absent ascites gives 1, and mild encephalopathy gives 2.

The total is 7, which lands in Class B rather than Class A. One 2-point criterion, the mild encephalopathy, tipped the verdict across the boundary.

Answer: Class B by a single point. This is exactly why the subjective grades must be recorded carefully: they can move the whole classification.

How to Interpret Your Class Verdict

Start with the class letter, because that is what clinicians quote. Then look at the total points to see where inside the class the patient sits: a 9 is a worse Class B than a 7, and the trend over time often matters more than any single score.

Read the per-criterion rows to find the drivers. A Class B driven by ascites and encephalopathy reads differently from one driven by bilirubin and INR, and it points the team toward different next steps.

Remember the verdict is a risk estimate for a population, not a prediction for a person. Two Class B patients can have very different operative risks depending on the operation planned and their other medical problems.

The Subjective Half: Ascites and Encephalopathy

Ascites grading rests on the physical exam and often on ultrasound: none means no detectable fluid, slight means fluid detectable but modest, and moderate to severe means obvious distension or tense ascites.

Encephalopathy grading follows the clinical scale from Grade 1, subtle changes like altered sleep or mild confusion, through Grade 2, drowsiness and disorientation, to Grades 3 and 4, stupor and coma.

Because these two are judgment calls, different examiners can score the same patient differently, which is one reason the score is best used alongside, not instead of, full clinical assessment.

Common Child-Pugh Mistakes

The most frequent error is mixing up the direction of the albumin bands: higher albumin is better, so above 3.5 is 1 point, not 3. Double-check this one every time.

Another common mistake is entering bilirubin in the wrong units. The score uses milligrams per deciliter; values in micromoles per liter must be divided by about 17.1 first.

A third mistake is treating the class as a hard rule for surgery. The operative mortality figures are historical averages, and modern perioperative care, the specific procedure, and the patient's trajectory all modify the real risk.

Where Child-Pugh Classification Is Used

Its original home was surgical risk assessment in cirrhosis: helping surgeons decide whether an operation was reasonable and helping patients understand the stakes. That remains its most quoted role.

Hepatologists also use it to track disease course. A patient drifting from Class A toward Class B over months is deteriorating, and the trend can prompt earlier transplant referral or closer surveillance.

Child-Pugh and MELD: Why the Verdict Still Matters

The MELD score, built from bilirubin, INR, and creatinine, now drives liver transplant allocation in many countries because it is fully objective and predicts short-term mortality well. It has partly replaced Child-Pugh in that setting.

Child-Pugh survives because it captures things MELD ignores: albumin, ascites, and encephalopathy. For surgical risk assessment and bedside grading of compensation, many clinicians still reach for it first.

Medical Disclaimer

This calculator and article are for informational and educational purposes only. They are not medical advice, and they do not establish a doctor-patient relationship.

Liver disease is complex, and no score captures every factor that matters for a real patient. Always discuss results with a qualified clinician, such as a hepatologist or the treating surgical team, before making any medical decision.

If you or someone you care for has liver disease, seek professional care promptly rather than relying on an online tool. In an emergency, contact local emergency services.

Frequently Asked Questions

1. What is the Child-Pugh score used for?

It grades the severity of liver dysfunction in cirrhosis, most famously to estimate surgical risk. The resulting Class A, B, or C verdict summarizes how compensated the liver is.

2. What are the five Child-Pugh criteria?

Total bilirubin, serum albumin, INR, ascites, and hepatic encephalopathy. Each scores 1 to 3 points, giving a total between 5 and 15.

3. What do the classes mean?

Class A, 5 to 6 points, means well-compensated liver function. Class B, 7 to 9 points, means significant functional compromise. Class C, 10 to 15 points, means decompensated disease.

4. What is the operative mortality for each class?

In the classic surgical literature, roughly 10 percent for Class A, 30 percent for Class B, and 80 percent for Class C. These are historical population averages, not individual predictions.

5. What is the one-year survival for each class?

Approximately 100 percent for Class A, 80 percent for Class B, and 45 percent for Class C in the traditional figures. Treat these as rough context, since modern care may differ.

6. Why is albumin scored in reverse?

Because higher albumin means better liver function. Above 3.5 g per dL earns the best score of 1 point, while below 2.8 earns 3 points. It is the one band people most often flip by accident.

7. How do I grade ascites?

None means no detectable fluid, slight means modest fluid detectable on exam or imaging, and moderate to severe means obvious or tense ascites. When unsure, describe what you see to the treating clinician.

8. How do I grade encephalopathy?

None is normal mentation, mild covers Grade 1 to 2 with subtle confusion or drowsiness, and severe covers Grade 3 to 4 with stupor or coma. Honest grading matters because it can tip the class.

9. Can the score change over time?

Yes, and tracking the trend is one of its best uses. A patient moving from Class A toward Class B is deteriorating, which can prompt earlier intervention or transplant referral.

10. What is the difference between Child-Pugh and MELD?

MELD uses bilirubin, INR, and creatinine and is fully objective; it drives transplant allocation in many countries. Child-Pugh adds albumin, ascites, and encephalopathy and remains popular for surgical risk and bedside grading.

11. Which units does the score use?

Bilirubin in milligrams per deciliter and albumin in grams per deciliter, with INR as a unitless ratio. Convert bilirubin from micromoles per liter by dividing by about 17.1 before scoring.

12. Is a Class C verdict an absolute ban on surgery?

No. The 80 percent figure is a historical average, and emergency life-saving surgery is still performed when there is no alternative. The verdict informs the discussion; it does not end it.

13. Who should interpret my Child-Pugh result?

A qualified clinician, ideally a hepatologist or the surgical team involved in your care. An online calculator can do the arithmetic, but only your care team knows the full clinical picture.

14. Does the score apply to liver disease without cirrhosis?

It was designed and validated for cirrhosis. Applying it to acute liver failure or non-cirrhotic liver disease stretches it beyond its evidence base, so clinicians use different tools there.

15. Is this calculator a medical device?

No. It is an informational arithmetic tool. It cannot diagnose, stage, or manage liver disease, and it must not replace professional medical advice, diagnosis, or treatment.