Convert Microgram to Stone (µg → st)

Converting micrograms to stones is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

1. 1
   Take your value in micrograms

   Start with the number of micrograms (µg) you want to convert.
2. 2
   Multiply by 1.575 × 10^-10

   The conversion factor from µg to st is 1.575 × 10^-10. Multiply your value by this number.
3. 3
   Read the result in stones

   The result is your value in stones (st).

Multiply the value in micrograms by 1.575 × 10^-10. For the reverse direction, multiply by 6,350,293,180.

• ✓1 µg = 0.001 mg = 1/1,000,000 g.
• ✓Some older labels write "mcg" instead of µg — both mean the same thing.
• ✓For very small doses prefer µg to avoid decimal confusion (0.025 mg vs. 25 µg).

• ✗Treating mcg and mg as equivalent on older prescription pads.
• ✗Typing "mg" when the intended unit is "µg" — a 1000× overdose.
• ✗Reading µg as g without the prefix — a 1-million-fold error.

What is the Microgram?

The microgram equals one millionth of a gram (10⁻⁶ g) and is the standard unit for very small mass measurements in pharmacology, environmental science, and trace-element nutrition. The Greek letter µ (mu) represents the SI prefix 'micro' (one millionth). Vitamin B12 daily intake is around 2.4 µg, and the lethal dose of botulinum toxin is in the nanogram-to-microgram range, making it one of the most potent biological substances known. The microgram is critical in air-quality monitoring (PM concentrations in µg/m³), trace-mineral supplements (selenium, iodine), and pharmaceutical compounding. It relates to the milligram (1,000 µg = 1 mg) and the nanogram (1,000 ng = 1 µg). Environmental regulators set legal limits on heavy metals (lead, arsenic) in drinking water in micrograms per liter.

• Vitamin D, A and K dosing
• Trace metal content in food and water
• Hormone replacement therapy dosing

What is the Stone?

The stone equals exactly 14 pounds or 6.35029318 kilograms and remains the traditional British unit for personal body weight. Originally based on a stone literally used as a counterweight on a balance scale, the unit was standardized at 14 pounds by an Act of Parliament in 1835. While metrication has reduced its role in commerce, the stone persists in British everyday life — a person is described as '11 stone 4' (158 lb) rather than 72 kg — and is widely used in British and Irish weight-loss programs, medical contexts, and gym equipment. The stone is virtually unknown in the United States and most of the world. It relates to the pound (14 lb = 1 stone), the kilogram (1 stone ≈ 6.35 kg), and the long ton (160 stone = 1 long ton). Stones-and-pounds notation (like '11 st 4 lb') is the British equivalent of decimal kilograms.

• Human body weight in the UK and Ireland
• British medical charts and patient records
• British boxing and wrestling press reports