Ounces to Daltons (oz to Da)
1 ounce equals 1.707248186×10²⁵ daltons (rounded).
How to convert ounces to daltons
To convert ounces to daltons, multiply the number of ounces by 1.707248186×10²⁵. The factor is rounded to 10 significant digits. To go the other way, multiply daltons by 5.857379193×10⁻²⁶ (rounded).
daltons = ounces × 1.707248186×10²⁵
Example: 10 ounces = 1.707248186×10²⁶ daltons.
Approximate value. Standards for the dalton varied by place and period, so this converter uses the most commonly cited value. Treat results as estimates, not exact figures.
About these units
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)
Dalton (Da)
About 1.66054×10⁻²⁷ kg, one twelfth of the mass of a carbon-12 atom. Used for atoms, molecules and proteins.
Chemists and biologists quote the mass of a protein as so many kilodaltons, a habit that goes back to John Dalton, who in 1803 suggested taking the lightest atom, hydrogen, as the natural yardstick for atomic weights. The unit itself took other forms for a long time. Around 1903 chemists settled on one sixteenth of an oxygen atom, and in 1960 and 1961 the physics and chemistry unions replaced that with a carbon-12 standard, calling it the unified atomic mass unit with the symbol u.
The name dalton, symbol Da, was proposed by IUPAC in 1993 and endorsed by IUPAP in 2005. It is the same unit as u and is defined as one twelfth of the mass of a free carbon-12 atom at rest in its ground state. The 2022 CODATA value, listed by NIST and in Wikipedia, is 1.66053906892 x 10^-27 kg, with a small uncertainty in the final digits. A helium-4 atom weighs about 4.0026 Da, and the giant protein titin about 3 to 3.7 MDa. The BIPM accepts the unit for use with the SI, and the 2019 redefinition of the kilogram left its definition unchanged.
1 dalton = 1.660539069×10⁻²⁷ kilograms (approximately).
Sources: Wikipedia: Dalton (unit); NIST CODATA: unified atomic mass unit
Related conversions
- Daltons to ounces (reverse)
- Ounces to kilograms
- Ounces to grams
- Ounces to metric tons
- Ounces to pounds
- Ounces to milligrams
- Ounces to micrograms
- Ounces to carats
- Ounces to stone
- Ounces to short tons
- Ounces to long tons
- Ounces to troy ounces
- Ounces to Earth masses
- Kilograms to daltons
- Grams to daltons
- Metric tons to daltons
- Pounds to daltons
See all weight & mass units.