Indirect Bilirubin — What It Means in Your Blood Test
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Indirect bilirubin is the form still waiting for your liver to process it.
Indirect Bilirubin captures the pigment that has not yet gone through processing. Reading this raw share separately helps show whether something upstream, before the pigment gets handled, is at play.
Also known as: Unconjugated Bilirubin, I. Bili, Indirect Bili, IBil
This isn't a case where higher or lower is better. Your body keeps it in a narrow band, and both directions can matter.
Last reviewed: 2026-08-16
What is Indirect Bilirubin?
This is the unconjugated fraction, carried in the blood attached to albumin because it does not dissolve in water. The liver later attaches a sugar group so it can be excreted.
Why is Indirect Bilirubin tested?
You have this test to look for faster red blood cell breakdown, or for your liver taking up bilirubin more slowly.
What is a normal Indirect Bilirubin range?
- India
- No India-specific national reference interval is published for this parameter; your lab's printed range is the most reliable comparison.
- Global
- 0.1–1.0 mg/dL
Ranges vary by lab, method and equipment — the range printed on your own report is the one that applies to your result.
Source: [AASLD, 2023]
What does your Indirect Bilirubin value mean?
There is no widely-accepted set of value bands for this parameter. Compare your result with the reference range printed on your own report, and discuss it with your doctor.
Indirect Bilirubin in mg/dL and SI units
Showing values in mg/dL. This is display only — your report's own value does not change.
| Value (mg/dL) | Same value (µmol/L) |
|---|---|
| 0.3 mg/dL | 5.1 µmol/L |
| 0.6 mg/dL | 10.3 µmol/L |
| 1 mg/dL | 17.1 µmol/L |
| 1.5 mg/dL | 25.7 µmol/L |
Source: [CLSI, 2010]
What does a high Indirect Bilirubin result mean?
A raised level can mean more red blood cells are breaking down, or your liver is taking up bilirubin more slowly. It is worth discussing with your doctor.
What does a low Indirect Bilirubin result mean?
A low level is normal and usually not a concern.
What can affect your Indirect Bilirubin result?
- Red blood cell breakdown
- Inherited traits (such as Gilbert syndrome)
- Liver uptake of bilirubin
- Some medicines
- Long fasting
Questions to ask your doctor
About this result
- What does my Indirect Bilirubin result mean for me specifically, given my age and health?
- Is my Indirect Bilirubin in the range that is right for me, not just the lab's general range?
What to do next
- Could anything I eat, do, or take have affected my unprocessed liver pigment result?
- Is there anything I should do about my Indirect Bilirubin, or is it fine to leave as it is?
About retesting
- Does my Indirect Bilirubin need to be repeated, and if so, when?
- The typical range for Indirect Bilirubin can vary between labs — should I compare my result against my own lab's printed range?
The bigger picture
- Should my Indirect Bilirubin be looked at together with my Total Bilirubin and Direct Bilirubin result?
- Does my Indirect Bilirubin connect to any condition I already have, or to anything I have noticed in how I feel?
Frequently asked questions
- What is Indirect Bilirubin?
- This is the unconjugated fraction, carried in the blood attached to albumin because it does not dissolve in water. The liver later attaches a sugar group so it can be excreted. You have this test to look for faster red blood cell breakdown, or for your liver taking up bilirubin more slowly.
- What is a normal unprocessed liver pigment range?
- A typical adult range is around 0.1–1.0 mg/dL. No India-specific national reference interval is published for this parameter; your lab's printed range is the most reliable comparison. Ranges vary by lab, method and equipment — the range printed on your own report is the one that applies to your result.
- What does a high Indirect Bilirubin result mean?
- A raised level can mean more red blood cells are breaking down, or your liver is taking up bilirubin more slowly. It is worth discussing with your doctor.
- What does a low Indirect Bilirubin result mean?
- A low level is normal and usually not a concern.
- What can affect your Indirect Bilirubin result?
- Several everyday factors can influence it, including Red blood cell breakdown, Inherited traits (such as Gilbert syndrome), Liver uptake of bilirubin, Some medicines, Long fasting.
Sources
- AASLD (2023) — Practice Guidelines on Evaluation of Liver Chemistry Tests
Part of the Liver Function
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