hs-CRP normal range: what your high-sensitivity CRP means

Quick answer: under 1.0 mg/L is low risk, 1.0 to 3.0 mg/L average and above 3.0 mg/L high cardiovascular risk (AHA/CDC statement, 2003; MedlinePlus). The 2018 AHA/ACC cholesterol guideline counts 2.0 mg/L or more as a risk-enhancing factor. Above 10 mg/L, set the result aside: look for an infection or inflammation, and retest at least two weeks after it has cleared.

Check hs-CRP with your lipidshs-CRP is on five SiPhox panels, alongside ApoB and LDL on most. $124 a test plus $25 shipping.

See SiPhox panels

hs-CRP normal range

MedlinePlus adds that most healthy adults have a CRP below 0.3 mg/dL (3 mg/L). The 2026 ACC/AHA guideline keeps hs-CRP on its list of markers used to refine heart risk.

How to read your result

1. Check the unit. The bands above are mg/L. If your report says mg/dL, multiply by 10 first.
2. Check the context. Were you ill, injured or recovering from something in the past two weeks? If so, the number is not a heart-risk reading.
3. Look for a second result. The AHA/CDC approach averages two tests taken about two weeks apart.
4. Read it with your lipids. A high hs-CRP matters most alongside a high ApoB or LDL, where it can tip a borderline decision about treatment.

mg/L or mg/dL?

This is the most common source of confusion with CRP. The heart-risk categories above are in mg/L. Some labs, and many standard CRP reports, use mg/dL, where the same amount is ten times smaller: 3 mg/L equals 0.3 mg/dL. Cleveland Clinic's general CRP page, for example, calls under 0.9 mg/dL normal and 1.0 to 10.0 mg/dL moderately raised; those are infection and inflammation ranges for standard CRP, not heart-risk bands. Check the unit before you compare.

What is hs-CRP?

C-reactive protein is made by the liver when there is inflammation anywhere in the body. A standard CRP test picks up the large rises seen with infection or injury. The high-sensitivity (hs) version measures the same protein but can read the low levels that matter for heart risk. Inflammation plays a role in plaque buildup, so a persistently raised hs-CRP adds to the picture from LDL, ApoB and Lp(a).

What high hs-CRP means

One high reading is not a diagnosis. hs-CRP jumps with a cold, a sore tooth or a hard workout, which is why the AHA/CDC statement asks for two measurements. Cleveland Clinic lists these causes of minor elevations:

• Obesity, diabetes, smoking, insomnia and depression
• Gum disease (gingivitis or periodontitis) and the common cold
• Pregnancy and recent injury

Women and older adults tend to run a little higher. Big rises (Cleveland Clinic's marked elevation starts at 10 mg/dL, which is 100 mg/L) point to bacterial or viral infection, major injury or vasculitis, and need a doctor. A persistent hs-CRP above 3 mg/L with no infection is a reason to review your whole heart-risk profile with your doctor.

Worked example: two tests, one average

Say a 50-year-old man who smokes and has gum disease gets an hs-CRP of 4.2 mg/L while feeling well, then 2.6 mg/L two weeks later. Following the AHA/CDC approach, his average is 3.4 mg/L: just above the 3.0 mg/L high-risk line. Both results are also over the 2.0 mg/L risk-enhancer mark in the 2018 guideline. Had either come back above 10 mg/L, the right move would have been to set it aside and look for an infection.

What might explain it: smoking and gum disease are both on Cleveland Clinic's list of causes of minor CRP rises, along with obesity, diabetes, insomnia and depression.

Questions to take to his doctor:

• Together with my LDL and ApoB, does an average hs-CRP of 3.4 mg/L change my overall risk or a treatment decision?
• Should my gum disease be treated first, with hs-CRP retested afterwards?
• What help is there to stop smoking?

What lowers hs-CRP

• Weight: Cleveland Clinic lists obesity among the causes of raised CRP, so losing excess weight removes one source.
• Tobacco: smoking raises CRP; stopping removes that source.
• Blood sugar: diabetes raises it, so better A1C control helps.
• Gums and sleep: treating gum disease and fixing poor sleep remove two listed causes.
• Medication: hs-CRP is one input to your overall heart risk, not a target on its own. If your risk is high, discuss treatment options with your doctor.

How to test hs-CRP

No special preparation is needed (MedlinePlus; Cleveland Clinic), and fasting is optional. For heart-risk assessment, the AHA/CDC statement recommends two tests about two weeks apart while you are well, then averaging them. Avoid testing during or just after a cold, flu or an injury, and repeat any result above 10 mg/L after you have recovered.

Which at-home tests include hs-CRP

hs-CRP is on five SiPhox panels: Longevity Essentials, Heart & Metabolic, Thyroid Focus, Ultimate 360 and GLP Optimization. Only Hormone Focus leaves it out.

Because repeat testing is part of reading hs-CRP properly, a subscription that retests every one or three months suits it well. SiPhox collects from the upper arm with no needle, and there is no included doctor review, so bring persistent high results to your doctor. Compare kits on our longevity blood test page or read the SiPhox review.

Most people start here

Longevity Essentials

$124 + $25 shipping per test

31 biomarkers per test

The default panel: heart, metabolic, hormone and inflammation markers in one draw.

Check price

Heart & Metabolic

$124 + $25 shipping per test

28 biomarkers per test

Lipids plus kidney and liver function: the panel for cardiovascular and metabolic risk.

Check price

Thyroid Focus

$124 + $25 shipping per test

21 biomarkers per test

A full thyroid workup including both thyroid antibodies, plus core lipids.

Check price

Two tests beat oneRetest hs-CRP monthly or quarterly and see your average, not a one-off.

Check SiPhox price

Frequently asked questions