Troy Pounds to Ounces (lb t to oz)
1 troy pound equals 13.16571429 ounces (rounded).
How to convert troy pounds to ounces
To convert troy pounds to ounces, multiply the number of troy pounds by 13.16571429. The factor is rounded to 10 significant digits. To go the other way, multiply ounces by 0.07595486111 (rounded).
ounces = troy pounds × 13.16571429
Example: 10 troy pounds = 131.6571429 ounces.
About these units
Troy Pound (lb t)
12 troy ounces (373.24 g). Formerly used for precious metals in the UK and US.
Twelve troy ounces made one troy pound, a heavier-feeling number than it sounds because the troy ounce itself is larger than the avoirdupois ounce. The pound holds 5,760 grains, which comes to about 373.24 grams, noticeably lighter than the 453.6 gram avoirdupois pound. The name probably points to the fairs of Troyes in France, although that origin is not certain.
Goldsmiths, silversmiths and mints used it for precious metals, and it was kept in the American system even though people rarely ask for it there today. In Britain the troy pound lost its official status in the nineteenth century, while the troy ounce stayed legal for precious metals.
Everyday use survives only through the ounce. Bullion prices are still quoted per troy ounce, which is one twelfth of this unit, so a troy pound corresponds to twelve of those bullion ounces.
1 troy pound = 0.3732417216 kilograms (exactly).
Sources: Wikipedia: Troy weight; Wikipedia: Pennyweight; NIST SP 811, Appendix B.8
Ounce (oz)
One sixteenth of a pound, exactly 28.349523125 g. Used for food, mail and consumer goods in the US and UK.
A twelfth part is what ounce originally meant. It comes from the Roman uncia, one twelfth of the Roman pound, a word that also gave English the inch. The abbreviation oz does not come from English at all but from the Italian onza or oncia. Over the centuries many regions and trades used different ounces: the English Tower ounce of 29.16 g was abolished by Henry VIII in 1527, and the Dutch ons was redefined as exactly 100 g in 1820.
The avoirdupois ounce used for everyday goods is one sixteenth of a pound, exactly 28.349523125 g or 437.5 grains, the standard in the US and under the UK imperial system. It is not the same as the troy ounce for precious metals, and neither is the fluid ounce, which measures volume. Ounces still describe portions such as steaks and burgers, and they show up in unexpected places: fabric is graded by weight per area, so a 16 oz denim is a heavy cloth, and the copper on a circuit board is specified in ounces, where 1 oz is roughly 34.7 micrometres thick.
1 ounce = 0.02834952313 kilograms (approximately).
Sources: Wikipedia: Ounce; NIST Guide to the SI, Appendix B.8 (mass conversions)
Related conversions
- Ounces to troy pounds (reverse)
- Troy pounds to kilograms
- Troy pounds to grams
- Troy pounds to metric tons
- Troy pounds to pounds
- Kilograms to ounces
- Grams to ounces
- Metric tons to ounces
- Pounds to ounces
- Milligrams to ounces
- Micrograms to ounces
- Carats to ounces
- Stone to ounces
- Short tons to ounces
- Long tons to ounces
- Troy ounces to ounces
- Daltons to ounces
See all weight & mass units.