FREE TOOLS

Blood pressure tools and calculators

Small, single-purpose calculators built on the same code as the BP Log app and the 2025 ACC/AHA guideline. They run in your browser and nothing you type is sent anywhere.

Results describe numbers. They are not a diagnosis, and your doctor reads them alongside your full history.

Check a reading

Put a single reading or test in context.

Category checker

Enter a blood pressure reading to see which 2025 ACC/AHA category it falls in, where it sits on the scale, and when a number needs prompt attention.

MAP and pulse pressure

Average one to three readings, then see pulse pressure and mean arterial pressure (MAP), worked out the same way as the BP Log app.

Orthostatic check

Compare a lying or sitting reading with standing readings at 1 and 3 minutes to see whether the drop meets the 20/10 mmHg orthostatic threshold.

Averages and patterns

Work with a set of home readings.

7-day home average

A guided 7-day home blood pressure log: two readings morning and evening, day 1 set aside, the rest averaged. Saves your progress in this browser and prints a summary for your doctor.

White coat check

Compare your office and home blood pressure averages against the 130/80 threshold to see whether the pattern is consistent with a white coat effect or masked hypertension.

Variability calculator

Paste or type your readings to see how much they vary: standard deviation, coefficient of variation and average real variability, for the top and bottom numbers.

Morning surge

Enter morning and evening home readings to see the morning-minus-evening difference in the top number, the home measure researchers use for morning surge.

Heart risk

Population risk estimates to discuss with a clinician.

PREVENT risk calculator

Estimate 10-year and 30-year risk of cardiovascular disease, heart attack and stroke (ASCVD), and heart failure with the AHA PREVENT equations used by the 2025 blood pressure guideline.

Reference

Charts, sizes and units.

Cuff size finder

Measure around your upper arm and find the cuff size the AHA lists for it: small adult, adult, large adult or adult thigh.

mmHg and kPa

Convert blood pressure between millimeters of mercury (mmHg) and kilopascals (kPa), in either direction.

Blood pressure chart

An interactive chart of the 2025 ACC/AHA blood pressure categories. Point to any top and bottom number to see its category, with a text table and why normal does not change with age.

BEFORE YOU MEASURE

Good numbers start with good readings

Every tool here is only as good as the readings you put in. Sit quietly for 5 minutes with your back supported and feet flat, use an upper-arm cuff that fits, and take two readings a minute apart. These guides explain why.

Track this automatically with BP Log.

The free iPhone app times two readings a minute apart, averages them, keeps your morning and evening numbers apart, and builds a report for your doctor.

Other ways to track: desktop, Excel and printable logs