What it does
A health log is just a dated list of numbers you measure yourself. This tool gives each kind a ready-made form: blood pressure, blood glucose, weight, sleep, a symptom diary, a period log, or a custom one with your own name and unit. Add entries as you go, and it draws a chart for each measure, works out weekly averages, and shows the lowest and highest.
It never says whether a number is good or bad. There are no categories or warning colours. If your doctor gave you a target, you can type it and a dashed line appears on the chart. Lab results go in lab results tracker, and health summary card makes a one-page summary for a new doctor.
How to use it
- Pick a log at the top. Set the unit if there is a choice (mg/dL or mmol/L, kg or lb).
- Check the date and time, fill in the boxes and press Add entry.
- Use From and To to pick a date range. Everything below follows it.
- Download the CSV, or the summary as a PDF, image or Word file, to show your doctor.
What each option does
- Unit switch changes how numbers are shown. Glucose is converted with ÷ or × 18.016, so no entry is lost.
- Your own target line is optional and only a line on the chart.
- Bring your own CSV adds entries from a file in the same layout as the download.
- Keep my logs on this device is off by default. Ticking it keeps your logs in this browser only; Clear all my logs deletes them.
Worked example
Sam records blood pressure on three mornings: 120/78, 130/80 and 140/82. The weekly table shows an average of 130 over 80 for the week of Monday 2 November. Sam types 120 as the target his doctor gave him, and a dashed line appears across the chart.
FAQs
Does it tell me if a reading is high? No. It only organises your numbers. Ask your doctor what they mean.
Where is my data? Only in the open page, unless you tick the keep box, and then only in this browser.
Can I move between devices? Download the CSV on one device and import it on another.
Where the numbers come from
- Blood glucose conversion: mg/dL ÷ 18.016 = mmol/L (the molar mass of glucose is about 180.16 g/mol). Weight: 1 kg = 2.2046 lb.
- Averages, lowest and highest are plain arithmetic. Weeks start on Monday. No guideline categories or colour bands are used; any target line is typed by you.
Standard scientific values, such as constants, atomic weights and melting points, are facts found in every textbook; we name where ours were checked. If you are an author or publisher and want a value, a credit or a table changed or removed, tell us and we will act quickly.
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Last updated 2026-11-10.