Convert Scruples to Kilograms

Convert Scruples (s ap) to Kilograms (kg) instantly and accurately.

Scruples (s ap)
Kilograms (kg)

Conversion Formula

kg = s ap × 0.0012959782

About Scruples

A scruple (s ap) is a unit of the apothecary weight system equal to 20 grains or approximately 1.296 grams. Derived from the Latin 'scrupulus' (a small sharp stone used as a counterweight), it was the basic dispensing unit in pre-metric pharmacy across Europe. The apothecary system divided the fluid ounce into 8 drams, each dram into 3 scruples, and each scruple into 20 grains - a hierarchy memorised by every 19th-century pharmacist.

About Kilograms

The kilogram (kg) is the SI base unit of mass - the fundamental unit from which all other mass measurements in the metric system are derived. Since 2019 it has been defined by fixing the Planck constant h to exactly 6.62607015 × 10⁻³⁴ J·s, replacing the 130-year-old International Prototype Kilogram (a platinum-iridium cylinder kept in Sèvres, France). The kilogram governs daily life worldwide: body weight in most countries, grocery shopping, luggage allowances, postal rates, freight pricing, and ingredient quantities in cooking all reference kilograms.

Quick Reference Table

Scruples (s ap)Kilograms (kg)
1 s ap0.00129598 kg
2 s ap0.00259196 kg
5 s ap0.00647989 kg
10 s ap0.0129598 kg
25 s ap0.0323995 kg
50 s ap0.0647989 kg
100 s ap0.129598 kg

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