Blood Pressure Checker

Category	Systolic	and/or	Diastolic
Low (Hypotension)	< 90	and/or	< 60
Normal	< 120	and/or	< 80
Elevated	120–129	and/or	< 80
High Stage 1	130–139	and/or	80–89
High Stage 2	≥ 140	and/or	≥ 90
Hypertensive Crisis	> 180	and/or	> 120

Understanding your blood pressure numbers

Blood pressure is expressed as two numbers: systolic over diastolic, written as 120/80 mmHg. The systolic number (top) is the pressure when your heart contracts; the diastolic (bottom) is the pressure when it relaxes between beats. Both numbers matter — you can have normal systolic pressure but elevated diastolic, or vice versa.

Regular home monitoring helps you and your doctor spot trends that a single clinic reading misses. Blood pressure naturally fluctuates through the day, rising in the morning and dipping at night. Tracking over days or weeks gives a far more accurate picture than any one-off measurement.

AHA blood pressure categories explained

The American Heart Association defines six ranges. Normal is below 120/80 mmHg. Elevated is 120–129 systolic with diastolic still under 80 — a warning to improve lifestyle before medication is needed. Stage 1 Hypertension is 130–139/80–89, Stage 2 is 140+/90+. A Hypertensive Crisis is above 180/120 and requires prompt medical attention. Hypotension (low blood pressure) is typically below 90/60 mmHg.

This tool classifies your reading against these ranges instantly and highlights readings that fall outside the normal zone so you know when to follow up with your doctor.

How to take an accurate home reading

Sit quietly for five minutes before measuring. Rest your arm on a flat surface at heart level, feet flat on the floor, back supported. Do not talk during the reading. Avoid caffeine, exercise, and smoking for 30 minutes beforehand. Take two readings two minutes apart and log the average — single readings can be misleading. Morning readings before breakfast and medication are most consistent.

What factors raise blood pressure temporarily

Blood pressure spikes after intense exercise, stress, cold weather, a full bladder, and even some over-the-counter medicines like decongestants and NSAIDs. White-coat hypertension — higher readings at the clinic due to anxiety — is common and is one reason home monitoring is so valuable. Track readings over time to distinguish temporary spikes from sustained hypertension.

Common use cases

Adults with a family history of hypertension use the checker daily alongside a home cuff to log morning readings and track whether their average is trending toward Stage 1 over weeks. Patients recently diagnosed with elevated blood pressure use the log to build a two-week record to share with their doctor at the next appointment, providing a more representative picture than a single clinic reading. Caregivers monitoring an elderly parent's blood pressure log readings after medication changes to observe whether the new prescription is bringing numbers into the normal range. Individuals making lifestyle changes — reducing salt or starting exercise — use the log to measure the impact of those changes on their readings over a month.

Frequently asked questions

What is a normal blood pressure reading?

According to the American Heart Association (AHA), a normal blood pressure is less than 120/80 mmHg. Readings between 120–129 systolic (with diastolic below 80) are considered Elevated.

What is systolic vs diastolic pressure?

Systolic pressure (the top number) measures the force when your heart beats. Diastolic pressure (the bottom number) measures the pressure between beats when your heart is resting.

When is blood pressure considered a hypertensive crisis?

A hypertensive crisis is when systolic pressure exceeds 180 mmHg or diastolic exceeds 120 mmHg. This requires immediate medical attention.

How does the reading log work?

Click 'Save to log' after entering a reading to add it to your session log. The log shows up to 20 recent readings along with the average systolic/diastolic values.

Is this tool a medical device?

No. This tool is for informational and educational purposes only. Always use a calibrated sphygmomanometer for clinical measurements, and consult a healthcare provider for diagnosis or treatment.

How often should I check my blood pressure at home?

For most adults, checking once or twice a day — morning before meals and evening before bed — gives a useful picture. Your doctor may suggest a specific schedule. Avoid measuring right after exercise, caffeine, or stress. Take two readings two minutes apart and log the average.

What lifestyle changes can lower blood pressure naturally?

Regular aerobic exercise (30 minutes most days), reducing salt intake below 5g per day, maintaining a healthy weight, limiting alcohol, not smoking, and managing stress through sleep and relaxation techniques can each lower systolic pressure by 4–10 mmHg individually. Combined, these changes can reduce the need for medication in Stage 1 hypertension.