MELD Score Calculator – MELD-Na & MELD 3.0

Compare MELD, MELD-Na and MELD 3.0

MELD-Na Score Formula

Formula

\[ \text{MELD(i)} = 10 \times \big( 0.957 \times \ln(\text{Cr}) + 0.378 \times \ln(\text{TBili}) + 1.120 \times \ln(\text{INR}) + 0.643 \big) \]\[ \text{MELD-Na} = \text{MELD(i)} + 1.32 \times (137 - \text{Na}) - 0.033 \times \text{MELD(i)} \times (137 - \text{Na}) \]

Where:

\(\text{Cr}\) — serum creatinine in mg/dL (floored at 1.0 and capped at 4.0; set to 4.0 if the patient had dialysis at least twice in the past week)
\(\text{TBili}\) — total serum bilirubin in mg/dL (floored at 1.0)
\(\text{INR}\) — international normalized ratio (floored at 1.0)
\(\text{Na}\) — serum sodium in mEq/L, clamped to the range 125–137

The first equation computes the original MELD score from kidney function, bilirubin and coagulation; the second adjusts it upward when sodium is low, reflecting the extra mortality risk that hyponatremia adds in advanced liver disease. The final score is bounded between 1 and 40.

MELD-Na Score – Calculation Example

Example: a patient has a total bilirubin of 2 mg/dL, an INR of 1.5, a creatinine of 1.2 mg/dL, a sodium of 134 mEq/L, and has been on dialysis twice in the past week. Because of the dialysis, creatinine is set to 4.0 mg/dL.

\[ \text{MELD(i)} = 10 \times (0.957 \times \ln 4.0 + 0.378 \times \ln 2 + 1.120 \times \ln 1.5 + 0.643) \approx 26.9 \]

\[ \text{MELD-Na} = 26.9 + 1.32 \times (137 - 134) - 0.033 \times 26.9 \times (137 - 134) \approx 28.2 \]

Result: a MELD-Na score of 28 (underlying MELD ≈ 26.9), corresponding to an estimated 3-month mortality of about 19.6%.

How to Use the MELD-Na Calculator

Enter your Serum bilirubin from your blood test report and choose the unit — mg/dL or µmol/L. If your report is in µmol/L, the calculator converts it automatically.
Enter your INR (international normalized ratio), which measures how quickly your blood clots.
Enter your Serum creatinine and select the correct unit, mg/dL or µmol/L.
Enter your Serum sodium in mEq/L. Values outside 125–137 mEq/L are clamped to that range, as required by the formula.
Tick the Dialysis at least twice in the past week checkbox if that applies — this sets creatinine to 4.0 mg/dL in the calculation.
Read your MELD-Na score, the underlying MELD score, the estimated 3-month mortality and an interpretation of what the score means.

What Is the MELD-Na Score?

The MELD-Na score (Model for End-Stage Liver Disease with sodium) is the standard tool used by transplant organizations such as OPTN/UNOS to rank patients with chronic liver disease for liver transplantation. It combines four routine laboratory values — bilirubin, INR, creatinine and sodium — into a single number from 1 to 40. A higher score means more severe liver disease and a higher risk of dying within three months, which translates into higher priority on the transplant waiting list.

The original MELD score used only bilirubin, INR and creatinine. However, low serum sodium (hyponatremia) was found to be an independent predictor of mortality in patients with cirrhosis and portal hypertension, so the sodium adjustment was added in 2016. Two patients with identical bilirubin, INR and creatinine values can have very different MELD-Na scores if their sodium levels differ: a sodium of 125 mEq/L can raise the score by roughly 6–10 points depending on the underlying MELD, while a sodium of 137 or above adds nothing.

The score is interpreted in broad bands. Below 15, liver function is relatively preserved and most centers do not list a patient for transplant, because the surgical risk would exceed the risk of the disease itself. Scores of 15–24 indicate moderate severity and usually trigger transplant evaluation. Scores of 25–34 indicate advanced disease with substantial short-term risk, and a score of 35 or above signals very advanced disease requiring urgent specialist care and high transplant priority.

Because MELD-Na relies on objective lab values, it reduces subjectivity in organ allocation. It is also useful in clinical discussions as a common language for disease severity — but it is a statistical estimate for populations, not a prediction for any individual patient.

Assumptions, Limitations and Practical Tips

Caps and floors matter. The calculator applies the official OPTN rules: bilirubin, INR and creatinine are floored at 1.0 (so values below 1.0 are treated as 1.0), creatinine is capped at 4.0 mg/dL, and sodium is clamped to 125–137 mEq/L. Entering a sodium of 120 or 145 produces the same result as 125 or 137, respectively.
Dialysis status changes the result significantly. If the patient received dialysis at least twice in the week before the lab draw, creatinine is set to 4.0 mg/dL regardless of the measured value. Always check this box when it applies.
Mortality figures are historical estimates. The percentages shown (about 1.9% for scores ≤9, 6.0% for 10–19, 19.6% for 20–29, 52.6% for 30–39 and 71.3% for 40) come from the original MELD validation cohorts. Modern treatment has improved survival in many bands.
The score does not capture everything. MELD-Na does not account for complications such as hepatic encephalopathy, variceal bleeding, hepatorenal syndrome in progress, or liver cancer (which is handled by a separate exception process). Patients with complicated disease may be sicker than their score suggests.
Use recent labs. Values from a single stable blood draw give the most meaningful result. If sodium or creatinine is changing rapidly, the score can shift noticeably from one week to the next.
This tool is not a diagnosis. A MELD-Na score is one input among many; discuss your results with a hepatologist or transplant center. If you are monitoring kidney function alongside liver disease, our eGFR calculator (CKD-EPI 2021) and dialysis dose (Kt/V) calculator may also be useful.

Related Calculators

Low sodium in liver disease often needs careful fluid management — see the free water deficit calculator for hypernatremia correction. If hyponatremia is caused or masked by high blood sugar, use the corrected sodium calculator to estimate the true sodium level.

Frequently Asked Questions

What is a normal or good MELD-Na score?

A MELD-Na score under 15 is generally considered relatively stable liver function. Scores of 15–24 indicate moderate disease, 25–34 advanced disease, and 35 or above very advanced disease with high short-term mortality risk. In the United States, transplant candidates must generally have a MELD-Na of at least 15 to stay active on the waiting list, because below that threshold the surgical risk outweighs the disease risk. Only a hepatologist can interpret your score in context.

How do I calculate MELD-Na by hand?

First compute MELD(i) = 10 × (0.957 × ln Cr + 0.378 × ln bilirubin + 1.120 × ln INR + 0.643), after flooring creatinine, bilirubin and INR at 1.0 and capping creatinine at 4.0 mg/dL. Then compute MELD-Na = MELD(i) + 1.32 × (137 − Na) − 0.033 × MELD(i) × (137 − Na), clamping sodium to 125–137 mEq/L. Finally, round to the nearest whole number and limit the result to 1–40. A scientific calculator or spreadsheet with LN and MIN/MAX functions handles it easily.

How do I convert bilirubin and creatinine from µmol/L to mg/dL?

Divide bilirubin in µmol/L by 17.1 to get mg/dL, and divide creatinine in µmol/L by 88.4 to get mg/dL. For example, a bilirubin of 34 µmol/L equals 2 mg/dL, and a creatinine of 106 µmol/L equals about 1.2 mg/dL. Many European and Asian lab reports use µmol/L, while the MELD-Na formula requires mg/dL. This calculator converts automatically when you select µmol/L, but always double-check which unit your report uses before entering values.

Why does my sodium below 125 or above 137 not change the score?

The OPTN/UNOS rules clamp serum sodium to the range 125–137 mEq/L inside the formula. A sodium of 120 is treated exactly the same as 125, and a sodium of 145 is treated the same as 137. This was done because the sodium adjustment was only validated within this range, and extremely low sodium carries risks that MELD-Na does not model. Severe hyponatremia (below 125) still needs urgent medical attention regardless of the score.

What is the difference between MELD and MELD-Na?

The original MELD score uses only bilirubin, INR and creatinine. MELD-Na adds a sodium adjustment, adopted by OPTN in 2016, because low sodium was shown to independently increase mortality in cirrhosis even when the other labs look stable. Two patients with identical bilirubin, INR and creatinine can differ by up to roughly 10 points if one has a sodium of 125 and the other 137. MELD-Na has replaced MELD for transplant allocation in the US.

Does MELD-Na apply to children?

No. MELD-Na was designed for adults with chronic liver disease. Children awaiting liver transplantation are scored with a separate system called PELD (Pediatric End-Stage Liver Disease), which uses bilirubin, INR, albumin, growth failure and age at listing rather than creatinine and sodium. If you are looking at results for a child, ask a pediatric hepatologist about the PELD score instead.

Why did my MELD-Na score drop even though I feel worse?

MELD-Na only captures four lab values, so it misses complications like hepatic encephalopathy, variceal bleeding, infections, or hepatorenal syndrome in progress. It also fluctuates with kidney function and sodium, which can change week to week — a single lab draw may look better than your overall condition. Patients with liver cancer or certain other conditions may also qualify for standardized exception points. Always discuss a mismatch between how you feel and your score with your transplant team.

MELD Score Calculator – MELD-Na and MELD 3.0