Toolbox
Blood Pressure Interpreter
Systolic and diastolic classified with metabolic context. Connects BP to insulin resistance, sleep, and mineral balance — not just sodium intake.
Your reading
mmHg
mmHg
Enter your systolic (top number) and diastolic (bottom number) from your most recent reading. Multiple readings averaged across days give a more reliable picture than any single measurement.
Medications that may affect your result
ACE inhibitors (lisinopril, enalapril) and ARBs (losartan, valsartan) lower blood pressure by relaxing blood vessels. Readings on these medications reflect the medicated state — your unmedicated pressure would be higher.
Beta-blockers (metoprolol, atenolol) lower both blood pressure and heart rate. May mask underlying blood pressure trends in either direction.
Diuretics (hydrochlorothiazide, chlorthalidone) lower blood pressure by reducing fluid volume. Can also affect electrolyte balance — potassium and magnesium levels should be monitored.
NSAIDs (ibuprofen, naproxen) can raise blood pressure, particularly with regular long-term use.
Decongestants (pseudoephedrine) and stimulants can transiently elevate blood pressure.
If you are on any of these medications, your reading reflects the medicated state. Discuss trends with your healthcare provider.
Frequently asked questions
What do the two blood pressure numbers mean?
The top number (systolic) is the pressure in your arteries when the heart beats; the bottom number (diastolic) is the pressure between beats, when the heart rests and refills. Both are measured in millimetres of mercury (mmHg) and written as systolic over diastolic — for example, 118/76. Both numbers matter: a problem in either one can move you into a higher category.
What's a normal blood pressure, and what are the stages?
Using the AHA/ACC categories: Normal is below 120/80. Elevated is 120 to 129 systolic and below 80 diastolic. Stage 1 is 130 to 139 systolic or 80 to 89 diastolic. Stage 2 is 140+ systolic or 90+ diastolic. A reading of 180/120 or above is a hypertensive crisis and needs urgent care. These are lower thresholds than older guidelines used, which is why some people who were “normal” now read as Elevated.
My two numbers fall in different categories — which one counts?
The higher category wins. Following AHA guidance, if your systolic and diastolic land in different bands, you are classified by whichever is more severe. So a systolic of 125 (Elevated) with a diastolic of 92 (Stage 2) is classified as Stage 2, not Elevated. The tool applies this rule automatically so you are not misled by the lower of the two numbers.
My reading was high once — do I have hypertension?
Not from a single reading. Blood pressure varies through the day and rises with stress, caffeine, a full bladder, talking, or a cold room — and “white-coat” elevation in a clinic is common. A diagnosis is based on multiple readings across different days, ideally including calm measurements taken at home. One high number is a reason to measure again carefully, not a diagnosis on its own.
How do I take an accurate reading?
Sit with your back supported and feet flat on the floor, arm resting at heart level, after five minutes of quiet rest — no caffeine or exercise in the preceding 30 minutes, empty bladder, and don’t talk during the measurement. Taking two or three readings a minute apart and averaging them beats a single inflation. Technique alone can shift a reading by 10 mmHg or more.
How is blood pressure connected to metabolic health?
Elevated blood pressure is one of the five components of metabolic syndrome, and it often travels with insulin resistance — chronically high insulin promotes sodium retention and stiffer blood vessels. So it tends to rise alongside a climbing fasting insulin, higher triglycerides, and increasing waist circumference, which is why it is one of the markers in the Metabolic Health Dashboard.
About this tool
Formula
Blood pressure is read directly from a sphygmomanometer (cuff). No formula — the values are read off the device. Best practice: seated, feet on floor, arm at heart level, after 5 minutes of rest, no caffeine or exercise in the preceding 30 minutes.
Classification
Based on AHA/ACC 2017 guidelines (maintained in 2025 update). Optimal (<110/70) and Healthy Range (110-119/70-79) are LLX sub-divisions of the AHA “Normal” category (<120/80), providing more granularity. Elevated: 120-129/<80. Stage 1: 130-139 or 80-89. Stage 2: ≥140 or ≥90. Hypertensive crisis: >180 and/or >120.
When values fall in different categories: the higher-risk reading determines the classification. This follows AHA guidance — a systolic of 125 with a diastolic of 92 is classified as Stage 2, not Elevated.
Known Limitations
A single office reading is the least reliable way to assess blood pressure. White coat hypertension (elevated readings in clinical settings) affects up to 30% of people. Home monitoring averages across multiple readings on different days are more informative. Blood pressure has significant diurnal variation — morning readings are typically higher. Arm position, cuff size, recent caffeine, and bladder fullness all affect accuracy.
Sources
Whelton PK, et al. 2017 ACC/AHA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults. Journal of the American College of Cardiology, 2018. 2025 AHA/ACC/Multisociety HBP Guideline update. Circulation, 2025.
Not sure what to do with this?
Foster offers direct one-on-one mentorship — a knowledgeable second set of eyes on where you stand, starting with a focused 30-minute consultation.
See how mentorship works →Educational tool only. Not for diagnostic purposes. Consult a healthcare provider for medical decisions.