About Child-Pugh Calculator
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Child-Pugh Calculator: Score Chronic Liver Disease Severity and Predict Survival
TL;DR: Five lab values and clinical findings produce a score from 5 to 15 that classifies chronic liver disease into Class A (5-6, 100% one-year survival), Class B (7-9, 80%), or Class C (10-15, 45%). The inputs are total bilirubin, serum albumin, INR, ascites severity, and hepatic encephalopathy grade. Clinicians use this score to guide transplant listing, surgical risk assessment, and treatment intensity. Enter your values above for an instant classification.
Table of Contents
- Five Numbers That Stage Liver Disease
- Six Clinical Scenarios Where the Child-Pugh Score Drives Decisions
- The Child-Pugh Scoring Formula and Classification Table
- How to Use the Calculator: Step by Step
- Putting the Formula to Work: Two Worked Examples
- Where People Go Wrong With Child-Pugh Scoring
- FAQ
- Assumptions and Notes
- What to Do After You Have Your Score
- Further Reading
Five Numbers That Stage Liver Disease
Chronic liver disease kills roughly 2 million people per year globally, and the trajectory from compensated cirrhosis to decompensation is not always obvious from a single lab value. The Child-Pugh score, originally published by Pugh et al. in 1973 as a modification of the earlier Child-Turcotte classification, compresses five clinical parameters into a single number between 5 and 15. That number predicts one-year survival, guides transplant candidacy, and determines whether a patient with cirrhosis can tolerate surgery.
Each of the five parameters (total bilirubin, serum albumin, INR, ascites, and hepatic encephalopathy) receives 1 to 3 points based on severity thresholds. The total maps directly to a class: A, B, or C. Class A patients have well-compensated liver disease with near-normal synthetic function. Class C patients have decompensated cirrhosis with a one-year survival rate under 50%. The biological mechanism is straightforward: as hepatocytes are destroyed and replaced by fibrotic tissue, the liver loses its ability to synthesize albumin, clear bilirubin, produce clotting factors, and detoxify ammonia. Each parameter in the score captures a different dimension of that decline.
Genetic variation in alcohol dehydrogenase and aldehyde dehydrogenase enzymes affects the speed at which alcohol-related liver damage accumulates, which is why two patients with identical drinking histories can present with very different Child-Pugh scores. The score itself does not account for etiology, only current function.
Plug your values into the calculator above and get your classification in seconds.
Six Clinical Scenarios Where the Child-Pugh Score Drives Decisions
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Evaluating transplant candidacy. Liver transplant waiting lists use the Child-Pugh score alongside MELD to prioritize allocation. A patient who crosses from Class A (score 5-6) to Class B (score 7+) enters a different risk category where transplant evaluation typically begins. In the United States, roughly 12,000 patients are on the liver transplant waiting list at any given time, and Class C patients receive priority.
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Assessing surgical risk in a cirrhotic patient. Elective abdominal surgery in a Class A patient carries a perioperative mortality rate of approximately 10%. That rate jumps to 30% for Class B and exceeds 80% for Class C. Surgeons use these numbers to decide between operative and conservative management, and a score difference of even 1 point near a class boundary changes the risk conversation.
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Monitoring disease progression over time. A patient with stable Class A cirrhosis who sees their score rise from 5 to 7 over 12 months has crossed into Class B. That two-point shift indicates accelerating decompensation and typically triggers more aggressive intervention, including increased surveillance intervals from every 6 months to every 3 months for hepatocellular carcinoma screening.
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Adjusting medication dosing. Many drugs are hepatically metabolized, and Class B or C cirrhosis significantly impairs clearance. Benzodiazepines, opioids, and certain antibiotics require dose reductions of 25-50% in Class B patients. A Child-Pugh score gives pharmacists and physicians a standardized framework rather than guessing based on individual lab values.
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Predicting variceal bleeding outcomes. Portal hypertension worsens as liver fibrosis progresses, and esophageal varices are present in about 50% of cirrhotic patients. A Class C patient who bleeds from varices has a 6-week mortality rate near 30%, compared to under 5% for Class A. The score determines whether prophylactic beta-blocker therapy or band ligation is indicated.
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Counseling patients and families on prognosis. A one-year survival rate is concrete. Telling a patient "you have cirrhosis" is vague. Telling a patient "your score is 11, which places you in Class C with approximately 45% one-year survival" provides a number that drives decisions about advance directives, treatment aggressiveness, and quality-of-life planning.
The Child-Pugh Scoring Formula and Classification Table
Each parameter is scored on a 1-to-3-point scale based on severity. The total of all five parameters determines the class.
Child-Pugh Score = Bilirubin points + Albumin points + INR points + Ascites points + Encephalopathy points
Range: 5 (best) to 15 (worst)
Parameter Scoring Table
| Parameter | 1 Point | 2 Points | 3 Points |
|---|---|---|---|
| Total Bilirubin (mg/dL) | < 2 | 2 - 3 | > 3 |
| Serum Albumin (g/dL) | > 3.5 | 2.8 - 3.5 | < 2.8 |
| INR | < 1.7 | 1.7 - 2.3 | > 2.3 |
| Ascites | None | Mild (diuretic-responsive) | Moderate to Severe (refractory) |
| Hepatic Encephalopathy | None | Grade 1-2 (mild confusion) | Grade 3-4 (stupor/coma) |
Classification and Survival
| Class | Score Range | One-Year Survival | Surgical Mortality | Clinical Status |
|---|---|---|---|---|
| A | 5 - 6 | ~100% | ~10% | Well-compensated |
| B | 7 - 9 | ~80% | ~30% | Significant functional compromise |
| C | 10 - 15 | ~45% | ~80% | Decompensated |
Source: Pugh RNH, Murray-Lyon IM, Dawson JL, et al. Transection of the oesophagus for bleeding oesophageal varices. British Journal of Surgery. 1973;60(8):646-649.
Limitations
The score has known blind spots. It does not capture renal function, which the MELD score addresses. Ascites and encephalopathy grading are subjective, introducing inter-observer variability of up to 1-2 points. And the score was originally validated in patients undergoing surgery for variceal bleeding, not the broad cirrhotic population where it is now applied. For transplant prioritization in the U.S., MELD has largely replaced Child-Pugh since 2002, though Child-Pugh remains standard for surgical risk stratification and clinical staging worldwide.
How to Use the Calculator: Step by Step
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Gather recent lab results. You need total bilirubin (mg/dL), serum albumin (g/dL), and INR. Results should be from the same blood draw or within a 48-hour window. Labs older than 30 days may not reflect current liver function.
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Assess ascites status. Select "None" if no fluid is detectable on exam or ultrasound. Select "Mild" if ascites is present but controlled with diuretics (spironolactone, furosemide). Select "Moderate-Severe" if ascites persists despite maximum diuretic therapy or requires paracentesis.
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Grade encephalopathy. "None" means no cognitive changes. "Grade 1-2" covers subtle personality changes, sleep disturbance, asterixis (flapping tremor), and mild confusion. "Grade 3-4" includes somnolence, marked confusion, stupor, or coma. If uncertain, the West Haven criteria provide standardized grading.
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Enter bilirubin in the first field. The default is 1.5 mg/dL. Normal range is 0.1-1.2 mg/dL; values above 2.0 begin accumulating extra points.
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Enter albumin in the second field. The default is 3.5 g/dL. Normal range is 3.5-5.5 g/dL. A value below 2.8 signals severely impaired hepatic synthetic function and receives 3 points.
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Enter INR in the third field. The default is 1.2. Normal is approximately 1.0. Values above 1.7 indicate significantly impaired clotting factor production. One non-obvious point: warfarin therapy artificially elevates INR and will inflate the Child-Pugh score if not accounted for.
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Read your result. The calculator returns your total score, the corresponding class (A, B, or C), and the associated one-year survival estimate. Discuss the result with your hepatologist or gastroenterologist.
Putting the Formula to Work: Two Worked Examples
Example 1: A 58-Year-Old Retired Teacher With Compensated Alcoholic Cirrhosis
Margaret was diagnosed with cirrhosis 3 years ago after decades of moderate-to-heavy alcohol use. She has been abstinent for 18 months. Her most recent labs show bilirubin 1.8 mg/dL, albumin 3.6 g/dL, and INR 1.3. She has no ascites on ultrasound and no signs of encephalopathy.
| Parameter | Value | Points |
|---|---|---|
| Bilirubin | 1.8 mg/dL (< 2) | 1 |
| Albumin | 3.6 g/dL (> 3.5) | 1 |
| INR | 1.3 (< 1.7) | 1 |
| Ascites | None | 1 |
| Encephalopathy | None | 1 |
Total: 5. Class A. One-year survival: approximately 100%.
Margaret's score is at the floor of the scale. Her liver function is well-compensated despite the cirrhosis diagnosis. She should continue abstinence, maintain hepatocellular carcinoma surveillance every 6 months with ultrasound, and repeat the Child-Pugh calculation at each follow-up to catch any upward drift early.
Example 2: A 44-Year-Old Warehouse Supervisor With Decompensated Hepatitis C Cirrhosis
David has hepatitis C cirrhosis diagnosed 5 years ago. He completed antiviral treatment and achieved SVR (sustained virologic response), but fibrosis had already progressed substantially. His labs show bilirubin 4.2 mg/dL, albumin 2.5 g/dL, and INR 2.1. He has refractory ascites requiring paracentesis every 2-3 weeks and Grade 1-2 encephalopathy managed with lactulose.
| Parameter | Value | Points |
|---|---|---|
| Bilirubin | 4.2 mg/dL (> 3) | 3 |
| Albumin | 2.5 g/dL (< 2.8) | 3 |
| INR | 2.1 (1.7 - 2.3) | 2 |
| Ascites | Moderate-Severe (refractory) | 3 |
| Encephalopathy | Grade 1-2 | 2 |
Total: 13. Class C. One-year survival: approximately 45%.
David's score places him firmly in Class C with severe decompensation. This result supports urgent referral for liver transplant evaluation. His MELD score should also be calculated for transplant listing priority. Elective surgery is contraindicated at this class. Medication dosing for any hepatically cleared drugs needs review, and his care team should discuss advance directives.
Where People Go Wrong With Child-Pugh Scoring
Using outdated lab values. Liver function can shift meaningfully within days during acute decompensation. Labs drawn 60 or 90 days ago may underestimate current severity by 2-3 points. Always use results from within the past 2-4 weeks, and preferably from the same blood draw.
Ignoring warfarin's effect on INR. A patient on warfarin with a therapeutic INR of 2.5 will score 2 points for INR regardless of actual liver synthetic function. This artificially inflates the total score by 1-2 points. If the patient is anticoagulated, note this limitation and consider using a pre-warfarin INR or adjusting interpretation accordingly.
Undergrading ascites. Mild ascites detectable only on ultrasound is still ascites. Clinicians sometimes mark "None" when a small volume of fluid is visible on imaging because the patient has no symptoms. That misclassification drops the score by 1 point, which can shift a borderline patient from Class B to Class A.
Confusing encephalopathy grades. Grade 1 encephalopathy presents as subtle sleep-wake cycle reversal or mild personality changes that family members notice but the patient does not. It is frequently missed or dismissed. Missing Grade 1 encephalopathy costs 1 point on the score and may delay recognition of worsening liver function.
Mixing up bilirubin units. The scoring thresholds above use mg/dL. Labs in many countries report bilirubin in micromol/L. The conversion factor is 17.1 (1 mg/dL = 17.1 micromol/L). A value of 51 micromol/L equals 3.0 mg/dL. Using the wrong unit without converting can shift the bilirubin subscore by 1-2 points.
Treating the score as a standalone decision tool. The Child-Pugh score was designed for population-level prognostication, not individual patient prediction. A Class B patient with a score of 7 and a Class B patient with a score of 9 have meaningfully different risk profiles despite sharing a classification. Always interpret the raw score alongside the class, and combine with MELD for transplant decisions.
Assumptions and Notes
- Margin of error. The subjective components (ascites grading and encephalopathy staging) introduce inter-observer variability of 1-2 points. Two clinicians grading the same patient may arrive at scores that differ by enough to change the class assignment at boundary values (6 vs. 7, or 9 vs. 10).
- Professional disclaimer. This calculator is an educational tool. Clinical decisions about transplant listing, surgical candidacy, and medication adjustment must be made by a qualified hepatologist or gastroenterologist using the full clinical picture, not a single score in isolation.
What to Do After You Have Your Score
The number tells you where the liver stands right now, not where it has to stay. A Class A result means the focus is on preventing progression: eliminating hepatotoxins, maintaining surveillance, and rechecking the score every 6-12 months. A Class B or C result means the conversation with your specialist should include transplant evaluation, medication review, and a clear plan for the next 90 days. Run your values through the calculator above and bring the result to your next appointment.