Convert Scruple (apothecary) to Carat (metric)
Convert scruples (apothecary) to carats (metric) instantly. 1 scruple (apothecary) = 6.479891 carat (metric) — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Carat (metric) to Scruple (apothecary) converter for the reverse conversion.
Units explained
Scruple (apothecary)
The apothecary scruple equals 20 grains, about 1.296 grams.
From Latin 'scrupulus', a small sharp pebble used as a tiny weight.
Historical apothecary dosing of powders.
Part of the apothecaries' system used through the 19th century.
Carat (metric)
The metric carat (ct) equals exactly 200 milligrams (0.0002 kg).
From Arabic 'qirat' and Greek 'keration', the carob seed once used as a counterweight.
The worldwide standard for gemstone and diamond mass.
The metric carat was fixed at 200 mg internationally in 1907.
Scruple (apothecary) to Carat (metric) conversion formula
The relationship between scruples (apothecary) and carats (metric):
To convert scruples (apothecary) to carats (metric), multiply the value in scruples (apothecary) by 6.479891. To reverse, multiply carats (metric) by 0.1543235835.
How to use this converter
Type a value into the calculator. The result in carats (metric) updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Carat (metric) to Scruple (apothecary) converter for the reverse direction.
Step-by-step: convert scruples (apothecary) to carats (metric)
- Write down the value in scruples (apothecary) (s ap).
- Multiply that value by the factor 6.479891.
- The product is the equivalent value in carats (metric) (ct).
- To reverse, multiply the carat (metric) value by 0.1543235835.
Worked examples
Example 1 — Convert 1 s ap to ct:
1 × 6.479891 = 6.479891 ct
Example 2 — Convert 100 s ap to ct:
100 × 6.479891 = 647.9891 ct
Real-world example — Adjacent small-scale precision
One scruple (apothecary) equals 1,000 carats (metric) — the standard sub-millimeter precision conversion that materials engineers use whenever they switch between bulk material thickness specs (larger unit) and surface-finish characteristics (smaller unit).
1 s ap × 6.479891 = 6.479891 ct
Real-world example — Adjacent metric sub-units
One scruple (apothecary) equals 1,000 carats (metric). Engineers move between these scales constantly: PCB feature sizes in the larger unit, wire-bond diameters in the smaller.
1 s ap × 6.479891 = 6.479891 ct
Scruple (apothecary) to Carat (metric) conversion table
Standard reference values for converting scruples (apothecary) to carats (metric):
| Scruple (apothecary) [s ap] | Carat (metric) [ct] |
|---|---|
| 0.01 | 0.06479891 |
| 0.1 | 0.6479891 |
| 1 | 6.479891 |
| 2 | 12.959782 |
| 3 | 19.439673 |
| 4 | 25.919564 |
| 5 | 32.399455 |
| 10 | 64.79891 |
| 20 | 129.59782 |
| 30 | 194.39673 |
| 40 | 259.19564 |
| 50 | 323.99455 |
| 100 | 647.9891 |
| 500 | 3239.9455 |
| 1000 | 6479.891 |
Frequently asked questions
How many carats (metric) is 1 scruple (apothecary)?
How do I convert scruples (apothecary) to carats (metric)?
How do I convert carats (metric) back to scruples (apothecary)?
How many carats (metric) is 100 scruples (apothecary)?
Popular weight unit conversions
Convert Scruple (apothecary) to other weight units
Show all Scruple (apothecary) conversions
Metric / SI (18 units)
Avoirdupois (15 units)
Troy & Apothecary (9 units)
Indian / South Asian (6 units)
Scientific / Atomic (9 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Sources & references
Conversion factor (1 s ap = 6.479891 ct) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.