AST to ALT Ratio Calculator

The AST to ALT ratio calculator helps you compare two liver enzyme levels. It uses AST and ALT blood test results. The result is also called the De Ritis ratio.

Our online AST ALT ratio calculator makes this calculation quick and simple. You only need your AST and ALT values. The calculator then divides AST by ALT.

This tool can also help you understand the basic pattern of your result. Still, the ratio is not a diagnosis. A doctor should review your full lab report and health history.

AST to ALT Ratio Formula

The AST to ALT ratio formula is simple.

AST to ALT ratio = AST ÷ ALT

For example, if AST is 80 U/L and ALT is 40 U/L:

AST to ALT ratio = 80 ÷ 40

AST to ALT ratio = 2.00

The result has no unit because both AST and ALT use the same enzyme unit.

The ALT to AST ratio calculator uses the reverse formula:

ALT to AST ratio = ALT ÷ AST

These are different calculations. If you want the standard De Ritis ratio, use AST ÷ ALT.

How to Use Online AST to ALT Ratio Calculator

1. Enter your AST value from your blood test.
2. Enter your ALT value from the same test.
3. Select the correct enzyme unit if the calculator asks for one.
4. Click the calculate button.
5. Read your AST/ALT ratio and the result category shown by the calculator.

Always enter values from the same lab test when possible. This gives a more useful comparison.

Example AST to ALT Ratio Calculation

Suppose your blood test shows:

AST = 120 U/L

ALT = 80 U/L

Use the AST ALT ratio calculation formula:

AST to ALT ratio = 120 ÷ 80

AST to ALT ratio = 1.50

So, the ratio of AST to ALT is 1.50.

Now consider another example.

AST = 150 U/L

ALT = 50 U/L

AST to ALT ratio = 150 ÷ 50

AST to ALT ratio = 3.00

Here, AST is three times the ALT level.

AST and ALT Ratio Interpretation

A ratio below 1 means ALT is higher than AST. A ratio near 1 means the two values are similar. A ratio above 1 means AST is higher than ALT.

A ratio above 2 can occur in some liver conditions, including alcohol-associated liver disease. However, the ratio alone can't tell you the exact cause of abnormal liver enzymes.

An AST/ALT ratio should always be viewed with the actual AST and ALT levels. Other liver tests, like those involving a Phosphorus Level Calculator, and clinical findings also matter.

Final Verdict

The AST to ALT ratio calculator uses one key calculation:

AST to ALT ratio = AST ÷ ALT

It is a fast way to compare AST and ALT blood test values. The result can help show whether AST or ALT is higher.

A higher AST/ALT ratio does not always mean cirrhosis. Many factors can affect AST and ALT. Muscle injury, alcohol use, medicines, liver disease, and other conditions may affect enzyme levels.

Use the calculator for a quick calculation, but don't use the ratio alone to make a medical diagnosis.

FAQs

What's a good AST/ALT ratio?

There is no single ratio that is considered “good” for everyone. A ratio below 1 is common in many forms of liver injury because ALT can rise more than AST. The result must be considered with the actual enzyme levels and clinical context.

How to calculate AST to ALT ratio?

Divide the AST value by the ALT value.

AST to ALT ratio = AST ÷ ALT

For AST of 100 U/L and ALT of 50 U/L, the ratio is 2.00.

Is an AST/ALT ratio of 1.3 a cause for concern?

A ratio of 1.3 alone does not establish a disease. It means AST is 1.3 times the ALT level. The actual AST and ALT values, other test results, symptoms, medicines, alcohol use, and medical history are also important.

Does high AST/ALT ratio always mean cirrhosis?

No. A high AST/ALT ratio does not always mean cirrhosis. AST can come from tissues outside the liver, including skeletal muscle. A high ratio can occur for several reasons. A healthcare professional should interpret the result with other clinical information.

What is the AST ALT ratio calculator MDCalc?

MDCalc is a medical calculation platform that provides clinical calculators. If you're looking for an AST ALT ratio calculator MDCalc, the key calculation remains AST divided by ALT. Always check the specific calculator and its clinical notes before using any medical result.

Can I use an ALT to AST ratio calculator instead?

Yes, but remember that ALT ÷ AST is the reverse ratio. It isn't the same as the standard AST ÷ ALT ratio. Check which ratio your calculator reports before interpreting the result.