Haemoglobin

Also called Hemoglobin, Hb, Hgb

What it measures

g/dL is the near-universal Indian and international convention, though g/L appears on some reports (simply the same number scaled by ten) and the German-language convention of mmol/L occasionally appears on imported lab software.

Haemoglobin below which anaemia is defined

CategoryValue
Children 6–23 monthsbelow 10.5 g/dL (105 g/L)
Children 24–59 monthsbelow 11.0 g/dL (110 g/L)
Children 5–11 yearsbelow 11.5 g/dL (115 g/L)
Children 12–14 yearsbelow 12.0 g/dL (120 g/L)
Women 15+, not pregnantbelow 12.0 g/dL (120 g/L)
Men 15+below 13.0 g/dL (130 g/L)
Pregnancy, 1st trimesterbelow 11.0 g/dL (110 g/L)
Pregnancy, 2nd trimesterbelow 10.5 g/dL (105 g/L)
Pregnancy, 3rd trimesterbelow 11.0 g/dL (110 g/L)

These are the 2024 revision, which lowered two of the older cutoffs — infants 6–23 months and the second trimester of pregnancy both moved from 11.0 to 10.5 g/dL. A report printed against the older figures may call a child anaemic who is not, by the current definition. WHO also directs that the measured value be adjusted for altitude and for smoking before it is compared to these cutoffs.

Source: World Health Organization, Guideline on haemoglobin cutoffs to define anaemia in individuals and populations (2024)

Reading it in a different unit

This lab reports Haemoglobin in g/dl. Reports from other labs — especially ones using European or US-style formatting — sometimes use a different unit for the same measurement. The relationship between them:

Reported unitHow it relates to g/dl
g/lg/dl = g/l × 0.1
mmol/lg/dl = mmol/l × 1.6114

Unit conversions verified against published molar masses and LOINC definitions. This is not a diagnostic reference — the normal range for any test is set by the laboratory that ran it and printed on your report.

Why this matters for tracking a trend

A value plotted next to earlier results only tells you something if every point is on the same scale. Two readings of the same test from two different labs, in two different units, can look like a dramatic change when nothing about your actual result changed — only the unit did. Converting to one scale before comparing is what keeps a trend line honest.

LOINC codes for this test: 30313-1, 30350-3, 718-7.

General information about laboratory measurement, not medical advice. Whether a specific result is normal for you depends on your lab's reference range, your history and your doctor's judgement — not on this page.