Understand your blood pressure
The first number is the peak of a pressure wave. The second is the level pressure falls to before the next heartbeat. The gap between them says something as well. Enter your reading and see what the machine is measuring.
120 / 80 mmHg
The category describes this value. A diagnosis normally rests on repeated measurements and, often, confirmation away from the clinic.
ESC 2024 · Table 5 · office/home/ABPM thresholds. AHA/ACC 2025 adult categories.
If there is chest pain, shortness of breath, new weakness, vision change or trouble speaking, call emergency services now. A hypertensive emergency is defined by acute organ injury together with very high pressure. Without acute symptoms, repeat the measurement after at least one minute. If it stays this high, seek prompt medical contact.
Under 18, adult tables do not apply. Paediatric BP depends on age and, in younger children, on sex and height percentile.
Assessment and treatment of blood pressure in pregnancy and postpartum follow specific guidance. This page does not calculate pre-eclampsia and does not replace obstetric care.
Only systolic pressure reaches the hypertension threshold (isolated systolic hypertension, using the ESC threshold for the chosen setting).
Only diastolic pressure reaches the threshold (isolated diastolic hypertension).
What does it mean physically? The peak and trough of the same arterial pressure wave in one cardiac cycle.
Which category is it in? Elevated BP
What does it mean for you? A single reading is not a diagnosis. Repetition, the place of measurement and clinical context still have to do the work.
Saved locally.
Local storage is unavailable. You can continue without a history.
Romanian and French often drop the final zero in speech. “14 with 9” or “14/9 de tension” is 140/90 mmHg. English usually says 140 over 90. It is the same unit.
| Said | Written |
|---|---|
| 12 over 8 | 120/80 mmHg |
| 13 over 8 | 130/80 mmHg |
| 14 over 9 | 140/90 mmHg |
| 16 over 10 | 160/100 mmHg |
120 mmHg is a pressure once represented by a mercury column about 120 millimetres high. Medicine kept the unit after the metal left the clinic. 1 mmHg ≈ 133.3 pascals, so 120 mmHg ≈ 16.0 kPa and 80 mmHg ≈ 10.7 kPa.
The heart pumps in pulses. Organs need nearly continuous flow. The elastic aorta reconciles the two: it expands in ejection and recoils in diastole. The curve below is arterial pressure, not an electrocardiogram. An ECG is electrical activity. 120 is the peak. 80 is the trough before the next beat. The distance between them is pulse pressure.
A simplified physiological model. It does not simulate a person’s blood pressure. The basic equation: C · dP/dt = Qin(t) − P/R.
Lower compliance, and the peak tends to rise while pulse pressure widens. Raise peripheral resistance, and pressure stays higher between beats. A larger stroke volume enlarges the oscillation. Rate changes how long diastole has to run off. Do not read clinical predictions from the slider.
The heart ejects, the aorta widens, stores energy and releases it gradually. The pressure wave is buffered.
The heart ejects, the vessel widens less, the peak rises more sharply. That is why arterial stiffness tracks especially with systolic pressure and pulse pressure.
ESC describes how blood pressure tends to move with age in populations. It does not say every person follows the same curve. Systolic pressure tends to rise into later life. Diastolic pressure rises until about the fifth or sixth decade, then may plateau or fall. Pulse pressure widens. The main mechanism is aortic stiffening. The numbers below illustrate the direction. They are not expected values for the age on the slider.
/ · PP
Averages move with age, especially systolic pressure. Current adult categories do not raise the hypertension threshold by decade. Age changes cardiovascular risk, treatment tolerance, frailty and therapeutic decisions. 150 does not become “normal” because someone is 75.
Pulse pressure is influenced by compliance, and also by stroke volume and wave reflection. A cuff is not an arterial-stiffness meter. Stiffness can be measured as pulse-wave velocity. ESC 2024 cites commonly used increased-risk thresholds around 10 m/s (carotid–femoral) and 14 m/s (brachial–ankle).
ESC 2024 · arterial stiffness as optional HMOD / risk modifier · cfPWV >10 m/s, baPWV >14 m/s.
PP = systolic − diastolic. 120/80 gives 40 mmHg, 140/90 gives 50, 150/70 gives 80. A wide pulse pressure is more common from middle age as large arteries stiffen. It also depends on stroke volume. 60 mmHg does not, by itself, mean “stiff arteries”. This page does not put PP on a universal traffic light.
A common approximation at resting rates: MAP ≈ diastolic + one third of pulse pressure, or (systolic + 2 × diastolic) / 3. For 120/80 that is about 93 mmHg; for 140/90, about 107. It is an approximation, not a measurement. Oscillometric cuffs detect oscillations and estimate systolic and diastolic values with device-specific algorithms.
With a cuff and stethoscope, the first Korotkoff sounds estimate systolic pressure; their disappearance estimates diastolic pressure. A digital monitor detects oscillations transmitted into the cuff. Those oscillations are largest around mean arterial pressure; an algorithm then infers the two displayed numbers.
130/80 in clinic is elevated BP under ESC 2024. Under AHA/ACC 2025 it is stage 1 hypertension. The disagreement is a difference of framework and wording. Cardiovascular risk moves continuously; thresholds help clinical decisions. Biology does not jump between 139 and 140.
ESC 2024 Table 5 versus AHA/ACC 2025 adult BP categories. Same 130/80, two labels.
120/80 mmHg is the familiar public benchmark. Under ESC 2024, a diastolic of 80 places it in elevated BP, because that category begins at 70. Under AHA/ACC 2025, the same 80 places it in stage 1 hypertension. Categories are management frames. One isolated measurement is not a diagnosis, and risk does not switch on at a single integer.
130/80 mmHg. ESC office: elevated BP. AHA/ACC: stage 1 hypertension.
140/90 mmHg. ESC office: the hypertension threshold is reached. AHA/ACC: stage 2. A diagnosis normally needs confirmation with repeated or out-of-office measurements, unless the clinical situation requires immediate management.
“From what number is it called hypertension?” is one question. “What pressure should treatment aim for?” is another. ESC 2024 keeps office ≥140/90 as the definition, and recommends, for many adults on BP-lowering therapy who tolerate it, an on-treatment systolic target of 120–129 mmHg, with exceptions for symptomatic orthostatic hypotension, age 85 and over, important frailty or limited life expectancy. The calculator does not prescribe drugs. Decisions depend on repeated BP, cardiovascular risk, existing disease and context.
ESC 2024 · treatment target 120–129 mmHg systolic when tolerated · exceptions age ≥85, symptomatic orthostatic hypotension, frailty, limited life expectancy.
ESC 2024: two measurements per session, 1–2 minutes apart, morning and evening, similar times, at least 3 days and up to 7, then the average. Morning readings before breakfast and medication, but not immediately after waking. Data stay on your device. No account.
Nothing leaves this device. The history lives only here.
1 · Morning
1 · Evening
2 · Morning
2 · Evening
3 · Morning
3 · Evening
4 · Morning
4 · Evening
5 · Morning
5 · Evening
6 · Morning
6 · Evening
7 · Morning
7 · Evening
Too small. Can raise the measured value.
A fit.
Too large. Can lower the measured value.
ESC describes a bladder about 75–100% of arm circumference, width 35–50%.
White coat: high in clinic, below threshold outside. Masked: below threshold in clinic, high at home or on ambulatory monitoring. That is why the place of measurement matters. ESC 2024 puts weight on out-of-office readings.
Neither is a fixed property, like height. Blood pressure moves with activity, posture, stress, temperature, sleep, medication timing, caffeine, a full bladder, circadian rhythm and measurement conditions. Clinical interpretation leans on repetition and averages.
Both. Their relative information changes with age. In younger adults, diastolic hypertension is more common. With ageing, aortic stiffness drives systolic pressure; isolated systolic hypertension is common in older adults, and systolic BP is particularly informative for cardiovascular risk. Do not discard the bottom number after 50.
A stiffer aorta expands less during ejection, so the peak rises. In diastole, pressure may fall a long way. The result is a wide pulse pressure. ESC links this phenotype to later life. In a young adult with the same pair, the physiology may differ; the group is mixed.
Systolic pressure is below 140, diastolic is not below 90. ESC office classification uses OR, not AND. Isolated diastolic hypertension is more common in younger adults than isolated systolic hypertension.
118/93: 118 does not rescue 93. 151/72: 72 does not rescue 151. The higher applicable category governs.
120 is a pressure peak, in mmHg. 80 is a pressure trough, in mmHg. 72 is beats per minute. A heart can beat fast with low BP, slowly with high BP, or “normally” with abnormal BP. There is no fixed conversion between pulse and blood pressure.
These are resting heart-rate ranges, not blood-pressure ranges. Source: MedlinePlus, reviewed 1 January 2025. AHA describes 60–100/min as the usual adult range; trained people may sit at 40–60. A pulse of 48 in a trained person without symptoms is not automatically pathological bradycardia.
| Age | Resting rate |
|---|---|
| 0–1 month | 70–190 |
| 1–11 months | 80–160 |
| 1–2 years | 80–130 |
| 3–4 years | 80–120 |
| 5–6 years | 75–115 |
| 7–9 years | 70–110 |
| ≥10 years and adults | 60–100 |
| trained athletes | sometimes 40–60 |
A low reading can be ordinary in a healthy person without symptoms. It becomes clinically important with fainting, severe dizziness, shock-like signs, dehydration, bleeding or drug effects. There is no universal red line such as 89/59 = danger. Numbers + symptoms + your usual baseline + context.
Rest seated or lying for 5 minutes, measure, stand, repeat at about 1 and/or 3 minutes. ESC: a drop of ≥20 mmHg systolic and/or ≥10 mmHg diastolic.
Older reference language kept 120/80 as a conventional “normal” mark. ESC 2024: below 120/70 non-elevated, 120–139 / 70–89 elevated, ≥140 / 90 hypertension. AHA/ACC 2025: below 120/80 normal, 120–129 and under 80 elevated, 130–139 or 80–89 stage 1, ≥140 or ≥90 stage 2. Thresholds are decision frames laid over continuous risk.
A cuff that is too small can produce a reading that is too high.
Unsupported arm: muscular effort breaks standardisation.
Talking: the conditions are no longer the protocol.
After coffee or exercise: guidance asks for about 30 minutes without stimulants or effort. The measurement is less reliable. Repeat it properly.
Under ESC 2024, in clinic, below 120 and below 70 is non-elevated. 120–139 or 70–89 is elevated BP. ≥140 or ≥90 is hypertension. 120/80, the familiar number, sits in elevated BP under ESC because of the diastolic value.
120/80 mmHg. ESC: elevated BP. AHA/ACC 2025: stage 1 hypertension, because 80 meets the American stage 1 threshold.
130/80 mmHg. ESC office: elevated BP. AHA/ACC: stage 1.
140/90 mmHg. ESC: hypertension threshold. AHA/ACC: stage 2. Diagnosis usually needs confirmation.
It reaches the ESC office hypertension threshold and AHA/ACC stage 2. One value is not, by itself, a diagnosis.
Systolic pressure: the arterial maximum in the cardiac cycle, during ventricular ejection and the pressure wave that follows.
Diastolic pressure: the arterial minimum before the next beat, from peripheral resistance, elastic recoil, heart rate and runoff into the microcirculation.
Both. With age, systolic pressure becomes particularly informative; the diastolic number is not ignored.
Systolic minus diastolic. It is not, by itself, a measure of arterial stiffness.
Isolated systolic hypertension, using the threshold of the setting. In older adults it often tracks a stiffer aorta; in younger adults the group is mixed.
Large arteries, especially the aorta, stiffen. Elastic recoil weakens, the peak rises, diastolic pressure may plateau or fall, pulse pressure widens.
In adults, 60–100 beats per minute at rest is the usual MedlinePlus and AHA range. Athletes may be below 60.
Newborns 70–190, then falling toward 60–100 from age 10. See the table. These are heart rates, not blood pressures.
Pulse counts beats. Blood pressure measures pressure. One does not convert into the other.
5 minutes quiet, no exercise, caffeine or tobacco for 30 minutes, back and arm supported, feet on the floor, correct cuff on a bare arm, two readings 1–2 minutes apart, morning and evening, 3–7 days, then the average.
For a home average, ESC asks for at least 3 days, ideally 7, with two measurements per session, morning and evening.
It may be a white-coat pattern: high in clinic, below threshold outside. Check at home or with 24 h monitoring, not with one visit.
Above threshold in clinic, below threshold at home or on ABPM.
Below threshold in clinic, above threshold at home or on ABPM.
At the first assessment both arms are measured. If systolic pressure consistently differs by more than 10 mmHg, later readings use the higher arm; a persistent difference may need clinical evaluation.
Above 180 and/or 120, repeat after a minute. With chest pain, breathlessness, a neurological deficit or other acute signs, call emergency services. A hypertensive emergency is defined by acute organ injury together with very high pressure. A persistently very high reading still needs prompt medical contact.
It can be ordinary without symptoms. With fainting, severe dizziness or shock it is a clinical problem, not a magic threshold.
Averages move, especially systolic pressure. Adult classification thresholds in ESC 2024 do not rise automatically by decade.
The heart pumps in pulses, and organs need nearly continuous flow. The aorta cushions ejection, small vessels control runoff into the tissues, and the cuff keeps the peak and the trough of the cycle. 140/90 tells you how high pressure climbs, how far it falls and how large the swing is. One measurement does not explain why it happened and is not enough for a diagnosis.
Guidelines used: ESC 2024 for the European classification, the default here, and AHA/ACC 2025 for adults in the American comparison. Checked on 16 September 2026. There has been no independent clinical review of this page. The information is educational, not personal advice.