Enter three systolic readings taken at different times. The tool computes the coefficient of variation, a marker that predicts outcomes beyond the average pressure.
Your visual report appears here
Fill in the form and press Calculate. You will get your number, an interpretation chip, and a personalized chart pack drawn instantly in your browser.
- Risk spectrum with your position marked
- Reference ranges from the original publication
- Shareable link, nothing stored
Scientific references
Why swings matter
Visit to visit variability in systolic pressure predicts stroke and heart events independently of the average level. Arteries dislike fluctuation as much as they dislike elevation.
The math
The calculator divides the standard deviation of your three readings by their mean and multiplies by one hundred, giving a percentage that compares across pressure levels.
Understanding your result
- Under 10 percent is stable
- 10 to 15 percent is moderate and common across days
- Above 15 percent deserves a look at timing, technique and medication consistency
Reducing noise
Measure at the same times daily, avoid caffeine beforehand and take readings seated after five minutes of rest before blaming biology.