How many avoirdupois ounces are in one scruple?

One scruple equals approximately 0.04571 avoirdupois ounces. About 21.88 scruples make one avoirdupois ounce. This crosses between the apothecary and avoirdupois weight systems.

How do I convert scruples to ounces?

Multiply scruples by 0.04571. For example, 10 scruples equals about 0.457 ounces. For quick estimation, divide scruples by 22 for approximate ounces.

Is the apothecary ounce different from the avoirdupois ounce?

Yes. An apothecary ounce equals a troy ounce (31.10 g), while an avoirdupois ounce is 28.35 g. The apothecary ounce contains 24 scruples; an avoirdupois ounce contains about 21.88 scruples. Same name, different weight, different internal structure.

Scruples to Ounces (s ap to oz) Converter

1 s ap = 0.0457 oz

1 Scruple equals 0.0457 Ounces (1 s ap = 0.0457 oz). Convert Scruples to Ounces with formula, table, and examples.

One scruple equals approximately 0.04571 avoirdupois ounces, meaning roughly 21.88 scruples make one avoirdupois ounce. This conversion crosses from the apothecary system to the avoirdupois system, connecting pharmaceutical dosing history with everyday weight measurement.

How to Convert Scruples to Ounces

oz = s ap × 0.0457142857

Multiply the value in Scruples by 0.0457142857

Take your value in Scruples
Multiply by 0.0457142857
Read the result in Ounces

Common Scruples to Ounces Conversions

Scruples (s ap)	Ounces (oz)	Status
1 s ap	0.045714 oz
3 s ap	0.137143 oz
5 s ap	0.228571 oz
10 s ap	0.457143 oz
20 s ap	0.914286 oz
24 s ap	1.097143 oz
50 s ap	2.285714 oz
100 s ap	4.571429 oz
200 s ap	9.142857 oz
288 s ap	13.165714 oz
500 s ap	22.857143 oz
1,000 s ap	45.714286 oz
5,000 s ap	228.571429 oz

Good to Know About Scruples to Ounces Conversion

The scruple-to-avoirdupois-ounce conversion was a daily reality for 19th-century pharmacists navigating between two weight systems. The apothecary system governed their training and prescriptions; the avoirdupois system governed their purchasing. Living in both worlds simultaneously required fluent cross-system arithmetic that modern pharmacists, working exclusively in metric, no longer need.

Scruples to Ounces: What You Need to Know

Pharmacists transitioning from apothecary to avoirdupois weights during the 19th century needed this conversion when bulk ingredients were purchased in avoirdupois ounces but prescriptions were written in scruples. Historical records from this transition period show both units on the same documents.

What is a Scruple? s ap

An apothecary scruple equals 20 grains or 1/3 of a dram apothecary (1.2959782 grams). A historical pharmaceutical unit largely replaced by metric measurements.

Apothecaries historical pharmacy historical medicine

Learn more about Scruple →

What is a Ounce? oz

An imperial and US customary unit of mass equal to approximately 28.35 grams. Commonly used in the US and UK for food and postal weight.

Imperial Us-customary food packaging (US/UK) postal weight cooking (US)

Learn more about Ounce →

Going the other way? Use our Ounces to Scruples converter.

Scruples to Ounces FAQ

One scruple equals approximately 0.04571 avoirdupois ounces. About 21.88 scruples make one avoirdupois ounce. This crosses between the apothecary and avoirdupois weight systems.
Multiply scruples by 0.04571. For example, 10 scruples equals about 0.457 ounces. For quick estimation, divide scruples by 22 for approximate ounces.
Yes. An apothecary ounce equals a troy ounce (31.10 g), while an avoirdupois ounce is 28.35 g. The apothecary ounce contains 24 scruples; an avoirdupois ounce contains about 21.88 scruples. Same name, different weight, different internal structure.

Non-Frequently Asked Questions About Scruples to Ounces

Questions nobody should ask - but someone did.

The box wins in practical terms: it uses avoirdupois ounces that your kitchen scale understands. A single serving of cereal at 1 ounce equals about 21.9 scruples, which sounds like a lot more cereal than it actually is. Marketing departments have not yet exploited this unit inflation opportunity.
A standard espresso shot weighs about 1 ounce (28.35 grams), which equals approximately 21.9 scruples. Your morning espresso is roughly 22 scruples of caffeinated liquid, which a Victorian pharmacist would have considered a dangerously large dose of stimulant, since caffeine in scruple quantities is indeed pharmacologically significant.
A trained apothecary would immediately notice the difference, since an apothecary ounce (31.10 g) is about 10 percent heavier than an avoirdupois ounce (28.35 g). Using the wrong ounce in pharmacy could produce a 10 percent dosing error, which for potent drugs could be the difference between treatment and toxicity. This is exactly why the metric system was so welcome in pharmacy.