Skip to content
Blood Test Tracker

TIBC by age and sex

What’s typical for TIBC at every adult age, from a U.S. government health survey of 8,158 people, next to the usual ranges labs print.

NHANES 2017–March 2020 (pre-pandemic)8,158 adultsAI-verified against cited sources. Awaiting expert review

What’s typical at one age

Pick a sex and an age to see the spread among U.S. adults like that, and type a result to see where it falls.

U.S. women aged 40–49

643 people in NHANES, 2017–March 2020 (pre-pandemic).

Women aged 40–49, 643 people: median 341, middle half 299 to 378, middle 90% 253 to 439 µg/dL. Usual range 250 to 450.

Median (half are lower)
341 µg/dL
Middle half of people
299 to 378
Middle 90% of people
253 to 439
Usual range a lab prints
250 to 450

Shaded: the middle 90% and middle half of people. Dark line: the median. The bracket above: the usual range.

Nothing you type here leaves your browser.

Across adult life

NHANES describes the US civilian, non-institutionalized population, not a 'healthy' reference group. People with disease, on medication, fasting or not (except fasting-subsample markers), smokers and so on are all included. A percentile says where a value sits among Americans of that sex and age, not whether it is normal.

How TIBC varies with age in the U.S.Shaded: middle 90% and middle 50% of people. Line: the median. µg/dL. Point at any age, or focus the chart and use the arrow keys, to read both sexes in words.

Use the left and right arrow keys to read each age. Shift moves five years.

Reference data derived from CDC/NCHS National Health and Nutrition Examination Survey (NHANES), cycles 2017-March 2020 (pre-pandemic). Analysis by bloodtesttracker.com; not endorsed by CDC, NCHS or HHS.

Every percentile

Download this table (CSV)

The 25th percentile means a quarter of people in that group had a lower result. In µg/dL. A dash means too few people were measured for the survey to publish that number.

Women

TIBC percentiles for U.S. women by age, in µg/dL, NHANES 2017–March 2020 (pre-pandemic)
AgePeople2.5th5th10th25thMedian75th90th95th97.5th
18–29750259276289313345382422444473
30–39645250268281301331367409435450
40–49643225253268299341378421439458
50–59733232252275297326356384407442
60–69736245258276294319349374397420
70–79400–252267295323354390428–
80+261–241250275307341372402–
All adults4,168243258275299330363403428450

Men

TIBC percentiles for U.S. men by age, in µg/dL, NHANES 2017–March 2020 (pre-pandemic)
AgePeople2.5th5th10th25thMedian75th90th95th97.5th
18–29745241255269291316342375395418
30–39531242247264285314346370387419
40–49601246256269287313338363384404
50–59629235251267289319344371396408
60–69775232242263290314344369397422
70–79438–235252279308336368387–
80+271–226244264295334363398–
All adults3,990236248263287314341369390412

About these numbers

  • NHANES describes the US civilian, non-institutionalized population, not a 'healthy' reference group. People with disease, on medication, fasting or not (except fasting-subsample markers), smokers and so on are all included. A percentile says where a value sits among Americans of that sex and age, not whether it is normal.
  • Assays differ between labs and between NHANES cycles. Values from a commercial lab can sit a few percent higher or lower than NHANES for the same blood. Earlier cycles were bridged to the 2021-2023 method with NCHS equations where NCHS recommends it.
  • Age 80 and over is top-coded at 80 in public NHANES files, so the 80+ cell mixes everyone 80 and older.
  • 2021-2023 (cycle L) had a 25.7% exam response rate and no race/income oversampling; NCHS advises caution when combining it with earlier cycles.
  • Frozen-serum iron panel (FETIB), 2017-March 2020 only.

Reference data derived from CDC/NCHS National Health and Nutrition Examination Survey (NHANES), cycles 2017-March 2020 (pre-pandemic). Analysis by bloodtesttracker.com; not endorsed by CDC, NCHS or HHS.

Centers for Disease Control and Prevention (CDC). National Center for Health Statistics (NCHS). National Health and Nutrition Examination Survey Data. Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, 2017-March 2020 (pre-pandemic). https://wwwn.cdc.gov/nchs/nhanes/

How we use survey data

The usual range at every age

The reference range labs print, for each age group. Ranges differ a little between labs, so the range on your own report is the one your result is judged against.

Use the left and right arrow keys to step through the age groups. Every range is also in the table below.

Usual range of TIBC by age, in µg/dL
WhoUsual range
under 0.2559–175 µg/dL
0.25–17250–400 µg/dL
18+250–450 µg/dL

Sources: ARUP Laboratories, Labcorp, MedlinePlus Medical Encyclopedia (NIH)