Scruple

Scruple is a unit converter that takes its name and its manner from the apothecary's bench. A scruple was a real measurement — one twenty-fourth of an ounce, the smallest weight a chemist would dose against a brass balance — and the word now lives on as a synonym for careful, considered attention. The app keeps both meanings in its design: a quiet apothecary green palette, brass and amber accents, italic serif labels like the ones written on old tincture bottles.

Pick a category, type a value, tap the unit you want to convert into, and the answer settles into the lower card formatted exactly to your chosen precision. Saved conversions are sealed into the Cabinet, where each entry is grouped by day and labelled with its category, source value, and converted result.

Ten measurement categories cover the conversions you actually reach for:

• Length — meter, kilometer, centimeter, millimeter, inch, foot, yard, mile, nautical mile

• Mass — kilogram, gram, milligram, metric ton, pound, ounce, stone

• Temperature — Celsius, Fahrenheit, Kelvin

• Volume — liter, milliliter, US/UK gallon, US fluid ounce, cup, pint, quart, cubic meter, cubic foot

• Area — square meter, square kilometer, square mile, square foot, square inch, hectare, acre

• Speed — m/s, km/h, mph, knots, ft/s

• Time — millisecond, second, minute, hour, day, week, year

• Data — byte, KB, MB, GB, TB, PB (binary, base-1024)

• Energy — joule, kilojoule, calorie, kilocalorie, watt-hour, kilowatt-hour, BTU

• Pressure — pascal, kilopascal, bar, atmosphere, PSI, mmHg, torr

Settings give you proper apothecary control:

• Decimal places, 0 to 8 — choose your precision

• Group thousands as 1,234,567 or run them flat

• Scientific notation for very large or very small results (1.23e+8)

• Default category to open the app in

• Haptic feedback on chip and button presses

• Two themes: a deep apothecary green dusk palette with brass and amber, and a cream parchment day palette with the same warm character

No accounts, no analytics, no syncing of any kind. Scruple runs entirely on your phone — your conversions and settings never leave the device.

A scruple, in the original sense, was the smallest amount worth weighing. Scruple the app does the same for everyday measurements: nothing too small to be done right.

Weighed with care.