On the heart-risk version of the test (hs-CRP), under 1 mg/L is lower risk, 1 to 3 is average and over 3 is higher. There is no single normal level for everyone. In a U.S. survey of more than 22,000 people, women and older adults had higher upper limits than men and younger people.
This article is part of our series on testing for inflammation. For every test and what each one shows, start with [How to test for inflammation](/articles/how-to-test-for-inflammation).
What is a normal CRP level? It depends on the question
C-reactive protein, or CRP, is a protein your liver makes when immune signals such as IL-6 (a messenger that inflamed cells send out) tell it to. Doctors measure it for two quite different reasons.
The first is to find and follow active inflammation, such as sepsis or an injury. Is something big going on? A standard CRP test answers that.
The second is to judge your chance of a heart attack or stroke years from now. That needs the high-sensitivity test, hs-CRP, which can read much smaller amounts. A 2016 review in a leading cardiology journal gave three bands: under 1 mg/L means lower risk, 1 to 3 means average, and over 3 means higher risk. In 2025, the American College of Cardiology said a high hs-CRP in people who seem healthy marks a higher-risk group.
So a reading of 4 mg/L can be fine on one report and a flag on another. It depends on which question the test was asked.
Does CRP go up with age?
Yes, on average. The largest study we found measured CRP in more than 22,000 Americans aged 4 and up, as part of a national health survey. The researchers looked at the 95th percentile: the level that only the top 5 in 100 people went above. That cutoff was lower in children than in older adults.
Readings of 3 to 10 mg/L turn up in about one third of Americans.From a 2006 review in Am J Med
For adults aged 25 to 70, they gave a rough rule for the upper limit. For men, it was age divided by 50, in mg/dL. Most lab reports use mg/L, which is 10 times larger, so a 50-year-old man's upper limit works out to about 10 mg/L. At 70 it is about 14 mg/L.
Those are upper limits for spotting disease, not targets. They mark where 95 in 100 people fell. And they sit far above the 1 mg/L line for heart risk.
What is a normal CRP level for a woman?
It tends to be higher than a man's. In the national survey, the 95th percentile was 0.95 mg/dL for men and 1.39 mg/dL for women (about 9.5 and 13.9 mg/L). The women's rule added 0.6 mg/dL to the men's at every age.
The Dallas Heart Study found the same gap. It measured CRP in 2,749 Black and white adults aged 30 to 65. The typical (median) level was 3.3 mg/L in women and 1.8 mg/L in men. More than half of white and Black women had a reading over 3 mg/L. The gap held after the team accounted for weight, estrogen use, statins and the usual heart risk factors.
Hormone therapy is not the main reason. In 28 trials with 3,360 women past menopause, low-dose hormone therapy did not change CRP compared with a placebo or a standard dose.
Pregnancy is a special case. A study that tracked 100 healthy pregnant women found a typical level of 4.12 mg/L in the third trimester, up from 2.39 mg/L in the first. The authors say pregnancy needs its own ranges, because CRP can rise late in pregnancy with no infection at all.
What else moves the number?
Body size is a big one. In 10,492 U.S. adults, a higher body mass index (BMI) and a larger waist were both linked to higher CRP, in men and women of every racial and ethnic group studied.
Race showed up in the data too. In Dallas, Black adults had a median of 3.0 mg/L and white adults 2.3 mg/L. The survey team suggested separate upper limits for Black adults. Nobody has settled whether heart-risk cutoffs should change by race or sex.
Small things count. A 2006 review found that even minor irritants can nudge CRP up, along with genes, diet and many conditions that don't seem inflammatory.
And one test is a snapshot. In 56,218 adults tested twice, two years apart, hs-CRP matched less closely from test to test than blood pressure, cholesterol or blood sugar did. Readings got steadier with age.
What this means for you
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your CRP is over 10 mg/L; you were sick, hurt or had surgery in the last few weeks; you have an autoimmune or other inflammatory condition; you are pregnant; or you take a statin, hormone therapy or any other medicine. Keep taking your medicine as prescribed, and talk to your provider before changing it.
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The bottom line
A woman of 60 and a man of 30 can get the same CRP result and mean different things by it. Age lifts the range. Being a woman lifts it more. Weight, pregnancy and last week's cold can all move it, and the next test may land somewhere else. That is why there is no single normal CRP level. There is a normal for the question your test was asking, and a normal for you. Find out which test you had, then read the number in that light.
Common questions
What is a normal CRP level for a woman?
For heart risk, the hs-CRP bands are the same for everyone: under 1 mg/L is lower risk, 1 to 3 average, over 3 higher. But women tend to read higher. In the Dallas Heart Study, the typical woman had 3.3 mg/L and the typical man 1.8 mg/L. In a large U.S. survey, women's upper limits were higher than men's at every age.
Does CRP go up with age?
On average, yes. In a U.S. survey of more than 22,000 people, the upper limit of CRP was lower in children than in older adults. For adults aged 25 to 70, the researchers' rough rule for the upper limit grew with each year of age. Older adults' readings also tend to be steadier from test to test.
What is the normal hs-CRP range?
A 2016 cardiology review set three bands for hs-CRP: under 1 mg/L means lower heart risk, 1 to 3 means average, and over 3 means higher. The 2025 American College of Cardiology statement says a high hs-CRP in healthy-seeming people marks a higher-risk group. These bands are for heart risk, not for finding an infection.
Can CRP be high for no clear reason?
Often, a little. Readings of 3 to 10 mg/L are found in about one third of Americans. A 2006 review linked minor rises to genes, diet, everyday irritants and many conditions that don't look inflammatory. Late pregnancy can lift CRP with no infection. So a slightly high result is a reason to talk with your provider, not to panic.
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How this article was made
Researched and written from 10 peer-reviewed papers. Our automated check matched every claim against the exact words of its source, confirmed every paper exists in PubMed, and found none retracted. Checked November 2, 2026. Not individually reviewed by a doctor. Photos are illustrative; the people in them are not patients or readers.
Grades run Strong, Moderate, Emerging, Early and Not supported, and the grade decides the words we may use. How we grade evidence · Medical disclaimer
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