Rheumatoid Factor (RF) Titer
An antibody linked to rheumatoid arthritis and other autoimmune conditions.
Consider this test if:
- Joint pain, morning stiffness, or symmetric swelling in the hands and feet
- Working up suspected rheumatoid arthritis alongside anti-CCP and CRP
- Symptoms of Sjogren's syndrome or another connective tissue disease
- Tracking a known autoimmune condition over time
Currently unavailable in your state.
This test isn't offered by labs in your state yet.
Pre-test considerations
No fasting required, and timing during the day does not matter. Recent or chronic infections can raise rheumatoid factor independently of autoimmune disease, which is worth noting if you have been ill.
Video consult with your Care Team
A 1:1 call to discuss your health.
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What this test is for
Rheumatoid factor is an antibody that targets the body's own immunoglobulins, and it is one of the standard markers used when evaluating inflammatory joint disease. Elevated RF is most associated with rheumatoid arthritis, where it helps support the diagnosis and signals a tendency toward more aggressive disease, but it also rises in Sjogren's syndrome, lupus, chronic infections, and sometimes in healthy older adults. It is commonly checked when joint pain, morning stiffness, swelling, and fatigue point toward an autoimmune cause rather than wear-and-tear arthritis. A positive RF does not confirm rheumatoid arthritis on its own, and a negative result does not rule it out, so it is read alongside anti-CCP antibodies, CRP, and the clinical picture.
This is the titer version, which reports the highest serum dilution at which RF is still detectable, giving a sense of how strongly positive the result is. The separate units/volume RF test reports a concentration in IU/mL, and the RF IgG test isolates the IgG antibody class for more specific autoimmune questions.
- Specimen
- Serum
- Measures
- Titer
What you'll learn
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Insights that connect the dots. A clinician reads your whole picture, not one result in isolation, connecting family history, past results, and lifestyle into clear next steps.
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Your personalized action plan. Nutrition, supplements, and training in one clinician-reviewed protocol, updated as your results change.
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Track your trends. Upload results from any lab and see each biomarker trend over time, so you know what is working.
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Never miss a recheck. Mito tells you what is worth retesting and when, then reminds you so nothing slips.
What to expect
- 1 Book instantly
Click, book, done. Choose a convenient lab location near you. Transparent, up-front pricing.
- 2 Quick lab visit
Testing to fit your busy schedule, usually 15 minutes or less. Walk-in and appointments available.
- 3 Typical results in 1-2 days
Your results post straight to your dashboard as soon as the lab completes them.
- 4 Expert guidance
Included with Mito membership. A clinician reviews your results and your personalized action plan follows, with clear next steps.
Everything your health needs,
in one membership
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Every test at our cost
Members pay our cost on every test, with lab fees passed straight through. The full receipt is itemized, never padded.
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Continuous tracking, all in one place
Upload past labs and watch your trends over time. Every marker and visit lives in one longitudinal record, so all your care stays together.
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Year-round clinician support
Text anytime and get clinician-reviewed answers. When you want to go deeper, 1:1 consultations are available at affordable rates.
All for $9/month
Order any test or consult without joining. For $9/month, members unlock member prices, trend tracking, and year-round clinician guidance.
Mito Membership
$9 /mo
cancel anytime
Without membership
$0
pay as you go
At-cost pricing on labs, scans, and more
Priority turnaround on your results
On-demand clinician consults when you need guidance
Personalized action plans across supplements, exercise, nutrition, and sleep
AI health coaching to help you act on your results
Year-round medical support, with in-chat clinician escalation
All your health records in one personal vault, with trends and biological age tracking
Early access to new diagnostics and product releases
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Frequently asked questions
View all FAQsHow does pricing work?
Every test shows the member price next to the standard non-member price, so you can see what membership saves you. The member price is our cost, covering the lab and what it takes to run the service. It is never a profit on the test itself. Mito makes its money on the $9 membership, not on marking up your tests. Membership is $9 per month, and any applicable lab order or draw fee is itemized before you pay.
Where do I get tested?
Choose an available partner lab at checkout. If your cart contains multiple blood tests, Mito helps consolidate the eligible tests at one lab when possible. At-home kits and scans follow the collection or appointment process shown on their product page.
Is this eligible for HSA/FSA?
Yes. Eligible tests can be paid for with an HSA or FSA card at checkout.
When will I get my results?
Your results appear in your Mito dashboard after the laboratory completes processing. A clinician then reviews them before your analysis and personalized action plan are finalized. Timing varies by test, and specialty assays and at-home kits may take longer.
Do I need a doctor's order?
No. Mito provides the laboratory order when one is required, so you do not need to arrange a separate doctor visit before purchasing.
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