Aldosterone to renin ratio calculator (renin activity)
A calculated ratio of aldosterone to plasma renin activity. Clinicians use it as a first step when looking into primary aldosteronism in people with high blood pressure. Type your results in the units on your report and it works out ARR as you type, in your browser.
AI-drafted. Awaiting verificationLast reviewed 2026-10-03Stress & Growth Hormones
Type your results above, or fill in the example, to see ARR.
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Educational information, not medical advice. Blood Test Tracker doesn’t diagnose or treat, and it doesn’t replace your clinician. Talk with your clinician before changing medications, supplements or care.
How it’s worked out
The formula
ARR = aldosterone (ng/dL) ÷ plasma renin activity (ng/mL/h). If aldosterone is in pmol/L, the ratio in pmol/L per ng/mL/h equals the ratio in ng/dL per ng/mL/h × 27.75.
A worked example
Example numbers, not anyone’s real results, run through the same code as the calculator above.
| Aldosterone | 10 ng/dL |
|---|---|
| Renin activity | 1.5 ng/mL/h |
| ARR | 6.7 ng/dL per ng/mL/h |
For an adult, this result is in the usual range.
What ARR tells you
Aldosterone and renin normally move in step: when renin falls, aldosterone should fall too. The ratio compares the two. A high ratio means aldosterone is high compared with renin, which can happen when the adrenal glands make aldosterone on their own. Labs get the ratio by dividing your aldosterone (in ng/dL) by your plasma renin activity (in ng/mL per hour), so it depends on both measurements.
The ratio is a first-step test, not a diagnosis. A result above the cut point is a reason for more testing. The Endocrine Society's 2025 guideline suggests testing aldosterone and renin in everyone with high blood pressure, because primary aldosteronism is often missed. The ratio can mislead, though. Medicines, potassium, salt intake and age can all push it up or down, so both false alarms and missed cases happen, and your own lab's cut point matters.
Read the full page on ARR, with what a high or low result can mean.
Usual ranges
The ranges the result above is placed on. Your own lab’s printed range comes first if it gives one.
- Adults0–30 ng/dL per ng/mL/h
Sources: Labcorp, ARUP Laboratories, ARUP Consult
Sources
The equation
- Aldosterone:Renin Ratio (test 004354), Labcorp
- Primary Aldosteronism: An Endocrine Society Clinical Practice Guideline, Journal of Clinical Endocrinology & Metabolism (2025)
3 more sources for the ranges and the explanation
- Aldosterone/Renin Activity Ratio (test 0070073), ARUP Laboratories
- Aldosterone-Renin Ratio (Test Fact Sheet), ARUP Consult (2026)
- Aldosterone (PubChem CID 5839), NCBI PubChem
AI-drafted. Awaiting verification. Last reviewed 2026-10-03. The calculator is version 1.0.0 of our code for this equation, tested against published examples. How we build and check these pages.