--- title: C-Reactive Protein Test type: biomarker url: "https://www.test-well.com/biomarkers/c-reactive-protein" also_known_as: - crp - c-reactive protein - c reactive protein category: Inflammation & Autoimmune units: - mg/L order_price_usd: 26.99 order_item: C-Reactive Protein (CRP) order_url: "https://www.test-well.com/tests/crp" reviewed_at: 2026-09-06 --- # C-Reactive Protein > C-Reactive Protein is measured with a standard blood draw; no fasting is needed. A typical reference range is 0.000 – 10.0 mg/L. At TestWell it's $26.99 all-in as C-Reactive Protein (CRP), results in 2–4 business days, drawn at Quest or Labcorp. An out-of-range result is a prompt to look closer, not a diagnosis. Also known as: crp, c-reactive protein, c reactive protein. ## Key facts | Fact | Value | | --- | --- | | Units | mg/L | | Sample | Blood draw | | Fasting | Not required | | Results | 2–4 business days | | Price | $26.99 | | Labs | Quest or Labcorp · BioReference in NY/NJ | ## What does C-Reactive Protein measure? A general marker of inflammation. The standard CRP test is less sensitive than hs-CRP and is used when active inflammation is suspected. ## What is the normal range for C-Reactive Protein? | Population | Reference range | | --- | --- | | age 18+ | 0.000 – 10.0 mg/L | Reference intervals differ slightly between labs; the range printed on your report is the one to interpret against. Ranges are usually set so 95% of healthy people fall inside them. ## What does a high C-Reactive Protein mean? Standard CRP rises within hours of infection, injury, surgery or an inflammatory flare and falls quickly once the cause resolves. Very high values (above ~100 mg/L) usually indicate bacterial infection or significant inflammation; moderate values are seen in viral illness, autoimmune disease, inflammatory bowel disease and after exercise or injury. It tells you inflammation is present, not where. ### Common causes of high C-Reactive Protein 1. Bacterial or viral infection 2. Injury, surgery, burns 3. Autoimmune and inflammatory conditions: rheumatoid arthritis, lupus, inflammatory bowel disease, vasculitis 4. Obesity, smoking (mild chronic elevation) 5. Cancer (some), pancreatitis ### Symptoms that go with high C-Reactive Protein - Depends on the cause — fever, pain, joint swelling ### What clinicians usually check next - Interpret with symptoms; repeat in 2–4 weeks once the acute illness passes - CBC, ESR; targeted tests for the suspected source - Persistent elevation without a cause warrants a clinician evaluation Follow-up tests at TestWell: [CBC with Differential](https://www.test-well.com/tests/cbc-with-differential) ($21.99), [CBC (Complete Blood Count)](https://www.test-well.com/tests/cbc) ($21.99), [Body Inflammation Test (ESR)](https://www.test-well.com/tests/sed-rate) ($18.99), [Sed Rate (ESR)](https://www.test-well.com/tests/sed-rate-esr) ($24.99). ### Seek care promptly if - A very high CRP with fever, severe pain or feeling very unwell — same-day care **What's the difference between CRP and hs-CRP?** Same protein, different sensitivity. hs-CRP measures precisely in the 0–10 mg/L range for heart-risk estimation; standard CRP is for detecting and tracking active inflammation and infection. ## What does a low C-Reactive Protein mean? A low CRP — including a result reported as 'less than' the detection limit — is the normal, desirable finding: it means there is no significant inflammation or infection being detected at the moment. It is not a deficiency and needs no follow-up on its own. For heart-risk assessment, a high-sensitivity CRP under 1 mg/L is the low-risk band. ### Common causes of low C-Reactive Protein 1. Normal health — most people without active infection or inflammation 2. Statins, aspirin and other anti-inflammatory medications lower it modestly 3. Weight loss, regular exercise, not smoking 4. Rarely, liver failure blunts CRP production during infection (very unwell people only) ### Symptoms that go with low C-Reactive Protein - None — a low CRP is the expected result ### What clinicians usually check next - No follow-up for a low value in a well person - If symptoms of infection or inflammation are present despite a low CRP, clinicians rely on the clinical picture and other markers (ESR, CBC), because CRP can lag the first 6–12 hours of an illness - For cardiovascular risk, ask for the high-sensitivity assay (hs-CRP), which resolves values below 1 mg/L Follow-up tests at TestWell: [CBC with Differential](https://www.test-well.com/tests/cbc-with-differential) ($21.99), [CBC (Complete Blood Count)](https://www.test-well.com/tests/cbc) ($21.99), [Body Inflammation Test (ESR)](https://www.test-well.com/tests/sed-rate) ($18.99), [Sed Rate (ESR)](https://www.test-well.com/tests/sed-rate-esr) ($24.99). **Is a low CRP bad?** No. CRP is produced in response to inflammation, so low means quiet — the result you want. There is no such thing as CRP deficiency. **What does CRP <0.3 or <1 mean?** The lab reports 'less than' when the value is below what the standard assay can measure. It's a normal result. A high-sensitivity CRP gives an exact number in that low range for heart-risk scoring. **Can you have an infection with a low CRP?** Early in an illness, yes — CRP rises over 6–12 hours and peaks around 48 hours. Some viral infections raise it only mildly. Symptoms matter more than the number in the first day. ## How do you get tested for C-Reactive Protein? | Order | Type | Price | Includes | | --- | --- | --- | --- | | [C-Reactive Protein (CRP)](https://www.test-well.com/tests/crp) | Single test | $26.99 | This marker | ## Quest vs Labcorp vs BioReference | Lab | Available | Price | Notes | | --- | --- | --- | --- | | Quest Diagnostics | Yes | $26.99 | Choose Quest at checkout; walk-in patient service centers in every state TestWell serves outside NY and NJ. | | Labcorp | Yes | $26.99 | Choose Labcorp at checkout; walk-in patient service centers in every state TestWell serves outside NY and NJ. | | BioReference (NY & NJ) | Yes | $20.99 | New York and New Jersey orders route here automatically — state rules keep Quest and Labcorp from accepting self-ordered draws. | ## Common questions about C-Reactive Protein ### Do I need a doctor's order to test my c-reactive protein? No. TestWell's licensed physician network reviews and approves your order — usually within minutes. You can place an order online without an in-person visit or a referral from your own doctor. ### How long does it take to get C-Reactive Protein results? Most C-Reactive Protein results are available in 1–3 business days after your specimen arrives at the lab. You'll get an email the moment your results are ready, with everything viewable in your TestWell portal. ### How much does a C-Reactive Protein test cost? Our C-Reactive Protein (CRP) starts at $26.99. That's the all-in price — no copays, no insurance hoops, no surprise bills. HSA and FSA cards are accepted. ### Do I need to fast before my C-Reactive Protein test? Fasting is not required for the C-Reactive Protein test. You can have your blood drawn any time of day. ### Which lab will process my C-Reactive Protein test? Your test will be processed by Quest Diagnostics, Labcorp, or BioReference depending on which is closest to you and which lab carries the test. All three are CLIA-certified and trusted by hospitals nationwide. You'll choose your lab during checkout from 4,000+ locations. ## Sources - [Mayo Clinic Labs](https://www.mayocliniclabs.com/test-catalog/overview/9731) - [MedlinePlus (NIH) — C-Reactive Protein (CRP) Test](https://medlineplus.gov/lab-tests/c-reactive-protein-crp-test/) ## Related biomarkers - [hs-CRP](https://www.test-well.com/biomarkers/hs-crp) - [ESR](https://www.test-well.com/biomarkers/esr) - [Tryptase](https://www.test-well.com/biomarkers/tryptase) - [Total IgA](https://www.test-well.com/biomarkers/total-iga) - [tTG-IgA](https://www.test-well.com/biomarkers/ttg-iga) - [Rheumatoid Factor](https://www.test-well.com/biomarkers/rheumatoid-factor) - [Reference range lookup tool](https://www.test-well.com/tools/reference-range-lookup) - [Lab unit converter](https://www.test-well.com/tools/lab-unit-converter) - [All biomarkers](https://www.test-well.com/biomarkers) --- Medically reviewed by Youmna DiStefano, MD (Medical Reviewer, TestWell); last reviewed 2026-09-06. Review policy: https://www.test-well.com/reviewers/youmna-distefano-md Canonical page: https://www.test-well.com/biomarkers/c-reactive-protein Machine-readable catalog: https://www.test-well.com/api/catalog.json · MCP server: https://www.test-well.com/mcp · Overview for agents: https://www.test-well.com/llms.txt Prices are cash-pay, in USD, and include physician authorization; every order adds one flat $6 lab processing fee. Educational content is not a diagnosis — discuss results with a clinician.