Liver risk check
NAFLD fibrosis score calculator
The NAFLD fibrosis score uses six routine numbers to estimate whether advanced liver scarring (fibrosis) is likely in a person who already has fatty liver disease. It is a risk estimate, not a diagnosis.
Your numbers
AST, ALT and albumin come from a liver panel or comprehensive metabolic panel; platelets from a complete blood count. Nothing you enter leaves this page.
What you will see
Your NAFLD fibrosis score, whether it falls in the low, in-between or high zone, and what that zone usually means.
Educational only, not medical advice. The score cannot diagnose liver disease.
Source
Angulo P et al., Hepatology 2007 (score and the -1.455 and 0.676 cutoffs). The formula as quoted from that paper in Angulo P et al., Gastroenterology 2013.
Validated in
733 adults with fatty liver disease confirmed by liver biopsy: 480 to build the score and 253 to check it.
Limits
Only for people who already have fatty liver disease. Not accurate under age 35, and less accurate in people with obesity or type 2 diabetes. Not for other liver diseases, heavy drinking or acute liver injury. It does not measure fat in the liver.
The formula
The score adds up six weighted numbers (Angulo 2013):
-1.675 + 0.037 × age (years) + 0.094 × BMI (kg/m²) + 1.13 × impaired fasting glucose or diabetes (yes = 1, no = 0) + 0.99 × AST/ALT ratio - 0.013 × platelets (×10⁹/L) - 0.66 × albumin (g/dL)
The study that built the score found that age, high blood sugar, BMI, platelet count, albumin and the AST/ALT ratio each pointed independently to advanced scarring (Angulo 2007). Older age, a higher BMI, diabetes and a higher AST/ALT ratio push the score up; more platelets and more albumin pull it down. If your lab reports albumin in g/L, the calculator divides it by 10.
The yes/no blood sugar item in the score is impaired fasting glucose or diabetes. The 2007 paper calls it hyperglycemia (Angulo 2007), and the authors' 2013 follow-up study, which used the original formula, defined hyperglycemia as a fasting glucose of 6.1 mmol/L (110 mg/dL) or more, or diagnosed type 2 diabetes (Angulo 2013). That is narrower than today's prediabetes, which also counts a fasting glucose of 100 to 125 mg/dL, an A1C of 5.7% to 6.4%, or a 2-hour glucose tolerance result of 140 to 199 mg/dL (ADA Standards 2026). Prediabetes found only on an A1C, or a fasting glucose under 110 mg/dL, falls outside the definition used in that 2013 study.
The cutoffs: -1.455 and 0.676
| Score | What it suggests | Source |
|---|---|---|
| Under -1.455 | Advanced scarring unlikely | Angulo 2007 (Angulo 2007) |
| -1.455 to 0.676 | In between: the score cannot rule scarring in or out | Angulo 2007 (Angulo 2007) |
| Over 0.676 | Advanced scarring more likely | Angulo 2007 (Angulo 2007) |
In the original study, a score under -1.455 ruled out advanced scarring correctly in 93% of the group used to build the score and 88% of the group used to check it (negative predictive value) (Angulo 2007). A score over 0.676 was right about advanced scarring in 90% and 82% (positive predictive value) (Angulo 2007). The AASLD 2023 guidance lists slightly rounded values, 0.672 or more and under -1.44 (AASLD 2023); we use the values from the original paper.
FIB-4 comes first
The American Association for the Study of Liver Diseases recommends FIB-4 as the first test for advanced scarring in people with fatty liver disease (AASLD 2023). Its guidance notes that the NAFLD fibrosis score is not accurate under age 35 and in people with obesity or type 2 diabetes (AASLD 2023). If you have AST, ALT and platelets, start with the FIB-4 calculator. The NAFLD fibrosis score adds BMI, blood sugar and albumin, and can be a second look at the same question. The APRI calculator was built for hepatitis C rather than fatty liver.
What the score says about the future
A later study by the same lead author followed 320 people with biopsy-proven fatty liver disease for a median of about 9 years (Angulo 2013). Compared with the low-risk group, people in the in-between and high-risk groups by this score had higher rates of liver-related complications and of death or liver transplant (Angulo 2013). The authors said the results still needed checking in other groups of patients (Angulo 2013).
Who should think about this
Fatty liver disease is common in people with overweight, type 2 diabetes or high blood pressure, and usually has no symptoms (NIDDK). Read fatty liver disease (MASLD), explained for the background. To compare your AST with your ALT on its own, use the AST/ALT ratio calculator. A high or in-between score is a reason to talk to your doctor about a second test, not a diagnosis of scarring.
Sources
- Angulo P, Hui JM, Marchesini G, et al. The NAFLD fibrosis score: a noninvasive system that identifies liver fibrosis in patients with NAFLD. Hepatology. 2007;45(4):846-854. PMID 17393509. pubmed.ncbi.nlm.nih.gov/17393509/
- Angulo P, Bugianesi E, Bjornsson ES, et al. Simple noninvasive systems predict long-term outcomes of patients with nonalcoholic fatty liver disease. Gastroenterology. 2013;145(4):782-789.e4. PMC3931256. pmc.ncbi.nlm.nih.gov/articles/PMC3931256/
- Rinella ME, Neuschwander-Tetri BA, Siddiqui MS, et al. AASLD Practice Guidance on the clinical assessment and management of nonalcoholic fatty liver disease. Hepatology. 2023;77(5):1797-1835. doi.org/10.1097/HEP.0000000000000323
- American Diabetes Association Professional Practice Committee. 2. Diagnosis and Classification of Diabetes: Standards of Care in Diabetes 2026. Diabetes Care. 2026;49(Suppl 1):S27-S49. doi.org/10.2337/dc26-S002
- National Institute of Diabetes and Digestive and Kidney Diseases (NIH). Nonalcoholic Fatty Liver Disease (NAFLD) and NASH. www.niddk.nih.gov/health-information/liver-disease/nafld-nash
Written and maintained by the uncovermyrisk.com editorial team. We do not have a medical reviewer; every claim links to its primary source above. Last reviewed: 2026-10-31. Spotted an error? See About.