Liver Function Test
An LFT is really two tests in one. ALT, AST, ALP and GGT are enzymes that leak out when liver cells are injured or bile flow is obstructed — they measure DAMAGE. Bilirubin, albumin and the clotting time measure how well the liver is actually WORKING. A liver can be badly damaged with normal function, and failing with only modest enzyme rises.
This is an educational reading aid, not a diagnosis and not medical advice. Reference ranges differ between laboratories — always read the range printed on your own report. Nothing here can see you, your history or your medicines. Do not start, stop or change any treatment on the strength of this page: take your report to a qualified doctor.
Reference ranges reviewed by Dr. Mohan Gayenlast reviewed
Your values
Fill in only the ones on your report. Anything you leave blank is simply skipped.
The yellow pigment from broken-down red cells. When it builds up, the eyes and skin turn yellow.
The processed fraction. A high proportion points towards a liver or bile-duct cause rather than red-cell breakdown.
The most liver-specific of the enzymes. It rises when liver cells are injured.
Found in liver, heart and muscle, so less specific than ALT.
From bile ducts and from bone.
Used mainly to tell whether a raised ALP is coming from the liver or from bone.
The main protein the liver makes. Because it lasts about three weeks in the blood, it reflects LONG-term liver function and nutrition.
Albumin plus all the globulins.
Enter one or more values and your reading will appear here.
What this panel is easy to get wrong
- AST also comes from muscle. A hard workout, an intramuscular injection or a muscle injury raises AST without the liver being involved at all.
- ALP comes from bone as well as bile ducts. It is normally high in growing children and in pregnancy.
- The PATTERN matters more than any single number: ALT and AST high together suggests liver-cell injury, while ALP and GGT high together suggests obstructed bile flow.
- Paracetamol overdose can cause severe liver injury with a normal-looking test in the first hours. Suspected overdose is an emergency regardless of blood results.
Where these ranges come from: Commonly published adult intervals. Enzyme upper limits differ noticeably between laboratories.
Where this is written from: This site is written from Indian clinical practice. Drug availability and brand names, vaccination schedules, national health programmes and some reference cut-offs differ between countries — a schedule or a threshold that is standard here may not be standard where you are. If you are reading outside India, check anything on this page against your own country’s guidance before you act on it.
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Bilirubin, ALT, AST, ALP, GGT, protein and albumin.