Calculates the aspartate aminotransferase to alanine aminotransferase ratio.
AST to ALT Ratio: Clinical Guide
Browse Knowledge HubCalculates the aspartate aminotransferase to alanine aminotransferase ratio.
Overview
Calculates the aspartate aminotransferase to alanine aminotransferase ratio.
Clinical Significance
Provides contextual information in liver injury patterns, but is non-specific and must be interpreted with absolute enzyme values, history and other investigations.
How It Is Calculated
- AST/ALT ratio = AST / ALT.
Interpretation
- Provides contextual information in liver injury patterns, but is non-specific and must be interpreted with absolute enzyme values, history and other investigations.
Worked Example
Enter a clinically consistent set of values in the displayed units. MedicalC applies: AST/ALT ratio = AST / ALT.
Limitations
- This tool does not establish a diagnosis or mandate treatment.
- Published cut-offs may vary between cohorts and measurement methods.
- Calculation precision cannot compensate for poor source data.
Clinical Pearls
- Trend the result over time where clinically appropriate.
- Record the source values and units alongside the calculated result.
Common Mistakes
- Using the wrong unit.
- Combining measurements obtained at different times.
- Applying a research-derived threshold as a universal treatment trigger.
Frequently Asked Questions
What does this calculator provide?
Calculates the aspartate aminotransferase to alanine aminotransferase ratio.
Can this result be used alone?
No. It must be interpreted with clinical context and appropriate investigations.
What equation is used?
AST/ALT ratio = AST / ALT.
What is the main limitation?
The result depends on valid inputs and may not be calibrated for every population or setting.
References
- De Ritis F et al. Serum transaminase activities in liver disease. Lancet. 1957. — Formula, physiological or validation reference.
Reviewed by: MedicalC Clinical Editorial Team
Last reviewed: July 2026
Clinical Disclaimer
MedicalC calculators and clinical tools are intended to support healthcare professionals. They do not replace clinical judgement, individual patient assessment, local guidance or specialist advice.
Results should always be interpreted in the context of the patient’s history, examination, investigations, current clinical condition and applicable professional guidance.