ALT is found mainly in the liver, while AST is also in muscle, heart and red cells. Alcohol damages mitochondria and depletes vitamin B6, raising AST relative to ALT.
How to use the AST/ALT Ratio Calculator
- AST
- ALT
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter AST and ALT from the same blood test.
Inputs explained
| Field | What to enter |
|---|---|
| AST | In U/L |
| ALT | In U/L |
Example values
How the main result changes when AST changes and everything else stays at the example values above:
| AST (U/L) | AST/ALT ratio |
|---|---|
| 40 | 1 |
| 60 | 1.5 |
| 80 | 2 |
| 100 | 2.5 |
| 120 | 3 |
| 160 | 4 |
Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.
Formula
AST/ALT = AST ÷ ALT
< 1: typical of fatty liver disease or viral hepatitis · > 1: possible cirrhosis · > 2: suggests alcohol-related liver disease
Worked example
Inputs — AST: 80 U/L; ALT: 40 U/L.
Results — AST/ALT ratio = 2; Pattern = Above 2 – suggests alcohol-related liver disease.
Key terms
- De Ritis ratio
- AST/ALT ratio.
Frequently asked questions
What is a normal AST/ALT ratio?
Around 0.8–1 in healthy people.
Does a high ratio always mean alcohol?
No – muscle injury, cirrhosis of any cause and some other conditions raise it.
What are normal AST and ALT levels?
Roughly under 40 U/L, depending on the laboratory.