# AST/ALT Ratio Calculator (De Ritis Ratio)

URL: https://speedycalculator.com/calculators/health/ast-alt-ratio/
Last updated: 2026-10-30

> The AST/ALT ratio calculator divides AST by ALT – the De Ritis ratio – which helps point towards the cause of liver damage: a ratio above 2 suggests alcohol-related liver disease, and above 1 can indicate cirrhosis.

## Inputs

- AST (U/L)
- ALT (U/L)

## Results

- AST/ALT ratio
- Pattern

## Formula

```
AST/ALT = AST ÷ ALT
< 1: typical of fatty liver disease or viral hepatitis · > 1: possible cirrhosis · > 2: suggests alcohol-related liver disease
```

## Explanation

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

FieldWhat to enterASTIn U/LALTIn 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 ratio401601.58021002.512031604
*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.*

## 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.

## FAQ

**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.


## Sources

- [Botros M, Sikaris KA. The De Ritis ratio: the test of time. Clin Biochem Rev, 2013](https://pubmed.ncbi.nlm.nih.gov/24353357/)