RA Factor: normal range and what it means
An antibody linked to rheumatoid arthritis.
Normal range
Adult reference range.
- Normal< 14 IU/mL
- Borderline14 – 20 IU/mL
- High≥ 20 IU/mL
What it measures
An antibody found in many people with rheumatoid arthritis, and in a fair number of healthy people too. A positive result alone does not make a diagnosis.
What moves it
Associated with rheumatoid arthritis, but also positive in some healthy people and in other conditions — so it is a pointer, never a diagnosis on its own.
How to bring it into range
Interpreted with symptoms, anti-CCP antibodies and inflammatory markers. A positive result without joint symptoms usually means little.
How fast it responds
Months.
Also reported as: rheumatoid factor · rf
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Common questions
- What is a normal RA Factor level?
- Normal: < 14 IU/mL. Adult reference range.
- What does a high RA Factor mean?
- A value above the reference band means RA Factor is outside the range typical for a healthy adult. A single reading is rarely conclusive on its own — what matters is the trend across draws and the other markers around it, which is why HealthOS reads the whole panel together rather than one number at a time.
- How do I improve my RA Factor?
- Interpreted with symptoms, anti-CCP antibodies and inflammatory markers. A positive result without joint symptoms usually means little.
More in Immunity & Other
Reference ranges are general-population guidance compiled from common clinical laboratories, not a diagnosis. Lab-to-lab ranges differ. Always read your results with your doctor.