Is hs-CRP Included in a Routine Blood Test?
No, hs-CRP is not part of most routine annual panels. A basic check often skips it, and that missing value is usually what stops the free PhenoAge calculator from working.
No. hs-CRP is not included in most routine blood tests. A standard annual panel usually covers fasting lipids, fasting glucose, a metabolic panel and a full blood count, but high-sensitivity C-reactive protein is a separate test order. If you tried the free PhenoAge calculator and could not complete it, missing hs-CRP is the most likely reason.
Is hs-CRP included in a routine blood test?
Most basic panels do not run it. If your report came from a standard wellness visit, look for a lipid profile, fasting glucose, a CBC and a CMP. hs-CRP is not hidden inside those. It is a separate test, often filed under inflammation, cardiovascular risk or infection markers. Some clinics run it as part of a wider cardiac risk panel, but that is the exception.
A basic panel shows glucose and lipids. hs-CRP shows a different layer, low-grade inflammation, and that layer is usually ordered separately.
Why it is the marker most often missing from the free PhenoAge calculator
PhenoAge, the biological age estimate published by Levine et al. in 2018, needs age plus nine routine blood markers. Eight of those come from a complete blood count and a comprehensive metabolic panel: albumin, creatinine, fasting glucose, lymphocyte percentage, MCV, RDW, alkaline phosphatase and white blood cell count. The ninth is C-reactive protein. The calculator accepts a standard CRP or a high-sensitivity CRP result, so you do not need a special assay if your lab already ran plain CRP. What you cannot do is guess. A fabricated CRP makes the biological age number meaningless.
What hs-CRP actually measures, and why a single result can mislead
CRP is a protein the liver makes largely in response to interleukin-6. It rises quickly during infection, tissue injury, autoimmune flares and heavy training. The high-sensitivity assay is not measuring a different protein. It simply reads lower concentrations more reliably than an older standard CRP test. A standard CRP may report down to about 3 or 5 mg/L. hs-CRP is designed to quantify changes below 1 mg/L, which is the range that matters for long-term cardiovascular risk and PhenoAge. After a strong trigger it usually begins rising within 4 to 6 hours and peaks around 36 to 48 hours. Its blood half-life is about 19 hours, so it falls quickly once the trigger is gone.
But a single reading is not a fixed trait. It can rise several-fold within hours of a viral infection or a hard workout, and it falls days later as the trigger resolves. That is why a result above 10 mg/L on the day of the draw usually points to an acute event, not a stable baseline.
In healthy adults, hs-CRP values are right-skewed. Many people sit below 1 mg/L, some sit between 1 and 3 mg/L, and a smaller group runs higher because of weight, smoking, poor sleep, inflammatory conditions or genetics. Oral contraceptives and pregnancy can also raise it. A jump from 0.5 to 6 mg/L after a respiratory infection is expected, not a new disease.
| hs-CRP result | What it usually means | What to do |
|---|---|---|
| <1 mg/L | lower relative cardiovascular risk | recheck if risk profile changes |
| 1-3 mg/L | average; may be affected by weight, sleep, smoking or minor inflammation | look at lipids, glucose and waist |
| >3 mg/L | higher relative risk; acute illness can also push it here | retest when well before interpreting |
| >10 mg/L | more likely infection or tissue injury than baseline | do not use for PhenoAge; wait and retest |
Scroll the table sideways for the rest →
Bands come from the American Heart Association and CDC hs-CRP categories. Above 10 mg/L usually reflects acute inflammation, not a stable baseline.
How to check an existing lab report for it
- Search the PDF or photo for "C-reactive", "CRP", "hs-CRP" or "high sensitivity CRP".
- It may sit under "Inflammation", "Cardiac risk", "Infectious disease" or "Special tests".
- If the result says "<0.3 mg/L", enter 0.3 in the calculator. Do not type "<0.3" as text.
- If only a standard CRP was run and the result is "<5 mg/L", the assay may be too blunt for the low-grade risk bands. hs-CRP is the better version for biological age and cardiovascular risk.
- If CRP is above 10 mg/L, treat that as a probable acute response. Retest when you are well before using it for PhenoAge.
When hs-CRP is worth adding
Add hs-CRP if you are building a biological age estimate, if you have a family history of early heart disease, or if you already track fasting glucose, HbA1c, triglycerides or waist circumference and want an inflammation signal alongside them. It does not require fasting and can be drawn at any time of day. The important condition is that you are well. Do not draw it two days after a fever, a vaccination, surgery or a major flare, because the number will reflect that event.
The HealthOS Blood Test includes hs-CRP. The collection method and the other markers vary by country, so the test page shows only what applies where you are.
What hs-CRP cannot tell you
hs-CRP is nonspecific. It does not identify where inflammation is coming from, and it is not a target in itself. Lowering a high number by treating the underlying cause is the goal, not chasing the CRP value with a supplement. If it is repeatedly high when you are well, running it alongside a lipid panel, HbA1c, fasting glucose, liver enzymes and a full blood count gives more useful context.
If you already have a report, the free HealthOS PhenoAge calculator fills itself from a screenshot or PDF once that report is read at /blood. Missing hs-CRP is the usual gap, and the tool shows it plainly instead of guessing.
Written by
HealthOS Research