Your Warfarin Diary
Built by a patient, for patients
Track INR • Manage doses • Stay safe
INR Trend - 14 Days
Track your INR with interactive charts and see trends over time
Built by Someone Who Lives It
In 2025, at 32, I had my chest cut open 3 times in 4 months. First for a bicuspid valve repair with Ozaki that failed. Then emergency surgery for a mechanical valve. Then again due to endocarditis. Now I'm on warfarin for life. I built CoagCompanion because I needed it.

Why CoagCompanion?
Managing warfarin shouldn't be confusing or scary
Paper logs are confusing
Scattered notes, lost papers, no trends. You deserve better than a messy notebook.
Forgetting your dose is scary
One missed dose can mean bleeding or clotting. You need reminders you can trust.
Vitamin K shouldn't be guesswork
Wondering if you can eat that salad? Our database has 200+ foods with exact vitamin K values.
Everything You Need
Simple tools for managing warfarin safely
INR Tracking with Trends
Log your INR and see trends over time. Know if you're staying in range.
Educational Resources
Understand how coagulation works, vitamin K interactions, when to seek help, and warning symptoms. The knowledge I wish I had from day one.
Vitamin K Food Database
200+ foods with exact vitamin K content. Know what you're eating.
Doctor Reports (PDF)
Generate professional reports for your appointments in seconds.
Simple, Honest Pricing
Built by a patient, for patients. No subscriptions, ever.
iOS App
Coming soon
Android App
Coming soon

Ready to Test at Home?
The CoaguChek INRange device brings lab-quality INR testing to your living room. No more waiting rooms, no more scheduling hassles.
- Professional-grade accuracy
- Results in seconds
- Test anytime, anywhere
- Medicare often covers
CoaguChek device sold separately. CoagCompanion is a free app to track your results.