Health & Body
Body measures, energy needs, cycles and sleep — every formula named, and none of it sent anywhere. All 15 of them run in your browser — nothing is uploaded.
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Body mass index in metric or imperial, with the caveats.
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Estimated daily energy needs, with the error bars stated.
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US Navy and BMI-based estimates, with their error range.
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Due date from a period, a scan or an IVF transfer.
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Next periods and fertile window, on a calendar.
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A Widmark estimate of BAC, with the legal limits.
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AHA and ESC categories from averaged readings.
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Du Bois, Mosteller, Haycock and Boyd side by side.
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Lab units between mg/dL and mmol/L, both ways.
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How much water a day, from weight and activity.
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Bedtimes and wake times in whole sleep cycles.
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Basal rate and daily calories, by three equations.
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Split daily calories into protein, carbs and fat.
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Four ideal weight formulas, and how far they differ.
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Five training zones from age or a measured maximum.
Other categories
- PDF Tools — Merge, split, compress, sign and convert PDF files without uploading a single page.
- Image Tools — Compress, resize, crop and convert photos with Canvas — the fastest tools on the site.
- Calculators — Percentages, loans, dates, mortgages and statistics, with the formula always shown.
- Converters — Units, temperature, time zones, data sizes and number systems.
- Text Tools — Count, compare, clean, transform and read text aloud.
- Developer Tools — JSON, Base64, hashes, regex, JWT and the rest of the daily toolkit.
- Design & Color — Colour conversion, palettes, gradients, shadows and accessibility checks.
- Generators & Security — QR codes, passwords, UUIDs, signatures, invoices and random pickers.
- Utilities & Media — Timers, recorders, device tests and archive tools that use your hardware directly.
- Office & Productivity — Spreadsheets, CSVs, timesheets, labels and the small jobs that eat an office afternoon.