Calculator
What the Blood Pressure Tracker does
Blood Pressure Tracker: calculates Category and Your Reading from Systolic (upper number) and Diastolic (lower number). Example: systolic (upper number) 120 mmHg and diastolic (lower number) 80 mmHg gives category Stage 1 Hypertension.
The inputs are Systolic (upper number) and Diastolic (lower number); the output is Category and Your Reading. There is no submit step; the numbers move as you adjust them.
It is mostly used by anyone curious about a reading. Population formulas give you a starting point, not a verdict about your body.
No sign-up, no data collection, no processing queue, just code running locally.
The field reference, the method and a worked example using the default inputs follow the tool itself.
What do the Blood Pressure Tracker fields mean?
The Blood Pressure Tracker uses 2 inputs. The starting figures are ordinary, not edge cases, so they make a sensible baseline.
| Field | What to enter | Default |
|---|---|---|
| Systolic (upper number) | measured in mmHg; accepts 70 to 250 | 120 |
| Diastolic (lower number) | measured in mmHg; accepts 40 to 150 | 80 |
How does the Blood Pressure Tracker work?
Each output is derived from the inputs above in a single pass; there is no hidden state carried between runs, so the same inputs always give the same calculation.
Each field is verified before use; failures are reported explicitly rather than swallowed.
Worked example
These are the values the Blood Pressure Tracker loads by default, and the result it produces from them. The defaults produce the result shown here; change any of them and the answer moves.
| Systolic (upper number) | 120 mmHg |
|---|---|
| Diastolic (lower number) | 80 mmHg |
| Category | Stage 1 Hypertension |
|---|---|
| Your Reading | 120 / 80 mmHg |
| What this means | Stage 1 high blood pressure. Lifestyle changes help; discuss with a clinician. |
How to use it
- Key in Systolic (upper number) in mmHg (70 to 250).
- Fill in Diastolic (lower number) in mmHg (40 to 150).
- No confirmation step: what you type is what gets calculated.
- Read Category, Your Reading and What this means in the results panel.
- If you need a record, Copy Link saves the inputs and Print produces a clean page.
What this tool does not do
- Body composition, ethnicity and age all shift what a "normal" result means for an individual.
- Population-level formulas cannot account for medical conditions, medication or pregnancy.
- Intermediate steps are rounded only for display; if you need full precision, work from the source figures.
- A plausible-looking answer from the wrong input is still the wrong answer: verify the fields first.
Frequently asked questions
Enter Systolic (upper number) in mmHg and Diastolic (lower number) in mmHg. Each field states its unit next to the input, and outputs are labelled the same way.
Systolic (upper number) accepts 70 to 250 mmHg. The range is enforced before the calculation runs, so a bad entry never reaches the formula.
With the values loaded when the page opens, category comes out as Stage 1 Hypertension. Edit any input and that figure moves with it.
No: there is no server involved. Close the tab and the values are gone.
No cost and no account. Use it as often as you like.
It is a screening estimate, not a diagnosis. The formulas are standard, but they describe averages and you are not an average. Use it as a starting point for a conversation with a professional.