Convert Mass from Stone to Microgram (st to mcg)

Stone to Microgram Conversion Formula

To convert from Stone (st) to Microgram (mcg), use the following formula:

With $453.59237$ is the ratio between the base units Gram (g) and Pound (lb).

Example

Let's convert 5 Stone (st) to Microgram (mcg).

Using the formula:

Therefore, 5 Stone (st) is equal to $31751465900$ Microgram (mcg).

What is a Stone (st)?

The stone (st) is a unit of measurement equal to 14 pounds (lb).

It's part of the imperial system and is still commonly used in a few countries, especially for weighing people.

How Many Kilograms are in a Stone?

For use in international contexts or scientific applications, the stone is often converted to the metric system.

One stone is equal to exactly 6.35029318 kilograms (kg).

This precise conversion is used in international trade and science to ensure everyone is using the exact standard measurement.

Why is Body Weight Measured in Stone?

Although it's an older unit, the stone remains the primary unit of measurement for body weight in the United Kingdom and Ireland.

It's common to hear someone state their weight as a combination of stone and pounds, like "12 stone 6 pounds."

Where Did the Stone Unit Come From?

The stone traces its origins back to the medieval English wool trade, where a "stone of wool" referred to a standard 14-pound measure used for buying and selling.

Stones for other goods could vary in weight—for example, a stone of glass was just 5 pounds—but over time, the 14-pound stone became the official legal standard.

What is a Microgram (mcg)?

A microgram (mcg) is a unit of mass equal to one-millionth of a gram.

Why Are There Two Symbols for a Microgram (mcg vs. μg)?

While the official symbol for the microgram in the International System of Units (SI) is μg (using the Greek letter Mu), you'll often see it written as mcg.

This is particularly common in the medical and pharmaceutical fields.

Using 'mcg' is a crucial safety measure to prevent dosage errors. A handwritten 'μg' could easily be mistaken for 'mg' (milligram), which would result in a 1,000-times overdose—a potentially fatal mistake.

Why Are Micrograms Important in Medicine?

The microgram is the go-to unit for measuring very potent substances, where tiny differences matter for both safety and effectiveness.

It's used for specific substances like:

• Vitamins (such as vitamin D, B12, and folic acid)
• Trace minerals (like iodine and selenium)
• Powerful medications (including certain thyroid hormones and chemotherapy drugs)

Measuring in micrograms makes it possible to give an effective dose without risking toxicity.

How Small Is a Microgram? A Visual Comparison

It's hard to picture how tiny a microgram is.

For perspective, a single grain of ordinary table salt weighs about 500–600 micrograms — meaning a single grain contains more than 500 micrograms.

That helps explain why we measure very potent substances in micrograms: their active doses are tiny.

What is the imperial system?

What is the metric system?

Stone to Microgram Conversion Table

Here are some quick reference conversions from Stone (st) to Microgram (mcg):